For many years I had been a traditional modeler. I created many miniatures of various airplanes, usually in my favorite scale – 1:24. Then converted into virtual modeling. (Look at some details about me and my previous projects). Having practical skill on both areas, I can to identify advantages and disadvantages of the "virtual aircraft":

• All what you need to create your favorite airplane are good scale plans and reference photos. You can build any aircraft you like from the scratch. In this hobby you do not depend on the availability of any particular kit on the market!
• You can apply to your model any painting scheme you want. It is the end of dependency on available decals. Most of the aircraft markings are created from simple, geometrical shapes. There is no problem to create them in an image processing program, and apply to the model as the textures. You will be able to prepare quickly even the smallest things - maintenance labels. (Well, maybe the font family of these inscriptions will be not exactly the same, as on the original airplane. If you do not want to draw a text as a painting, you are restricted to the fonts available on your computer. Fortunately, the difference is practically not visible on the final renderings)
• Virtual modelling is probably the cheapest kind of the hobby. Plenty of secondary materials, like photos, is available on the net. Sometimes you have buy a monograph of an airplane, to get a decent scale plans and reference materials you cannot find online. And that's all! Probably your computer is turned on for the most of the day, so it should have no impact on your bills for the power supply.
• You can always update your model. Even when the it is finished. For example, when you find, at the end of the work, that fuselage shape differs from the original, you can still modify it. Nothing is left to the chance. The same applies to the paintings.
• You can create objects with precision, which is impossible to obtain in the real world. It may lead to aberrations, when you will try to make too “ideal” things. (Sometimes I had caught myself on spending many hours on “polishing” a small detail, which is hardly visible on the final picture.)
• All multiplied parts are easy to create. Just define a half of one cyllinder from a radial engine. Mirror it, to create the symmetrical, opposite side. Then duplicate this object around the carburetor. When I did it for the first time, I was astonished, that such interesting final effect requires so little work. There is also no special problem with duplicating your model into a squadron of planes. (Maybe it is good idea to start experiment with such group, using low-poly version of your aircraft. It is easier to manipulate them en masse, at least!).
• You can easily duplicate whole model, when you wish. It is a common property of all entities on a computer. This way you can also easily share your model with the others.
• This is a “clean” work: no splashes of the paint, no drops of the glue on your table and clothes. (Have the other members of your family complained about them?) It can be also more environment-friendly hobby (just do not print too much...)
• Have you thought about making movies with your model? It is possible – at least a few-minute animation sequences!
• The 3D printers are coming! Their prices decrease every year, while their precision constantly improves. I think that within a few years you will be able to design and produce your own plastic model kit. In this way the computer modeling will connect the plastic modeling. (Currently the plastic kit factories prepare the new models using their CAD systems. Within a few years you will get similar possibility for yourself!)

• You cannot touch the model. It is obvious. During the work over a real object, the modeller often checks “by touch” some details of the surfaces. This "sensoric" way of working is impossible, here. (There is a long tradition of making ship models in the bottles. Such way of modelling is similar to the situation in 3D graphics. You cannot touch them there, either. But probably you have not practising this kind of hobby). On the other hand - by practising the computer modeling you can prepare your workshop for the incoming 3D print technology...
• There are no counterparts of the plastic model kits. You can find certain number of finished 3D models on some sites. The problem is, that they cost a lot, and amount of the work required to check and adapt them for your particular needs is relatively high. (There may occur problems with conversion from other file formats, in other cases - some nasty simplifications of important details). Usually you have to built your models from the scratch (from the scale drawings).
• Modeling in 3D usually takes more time (it depends on the situation – 50%? 100%?), than making traditional models. The reasons for this phenomena is not only the lack of a counterpart of a model kit. It seems that computer encourages the user to dig too deeply into details! Many 3D modelers cannot resist the temptation to do everything properly up to the smallest unit. They often have forgotten, that the real surface was often less ideal than its 3D copy, that they are working on.

There are some possible workarounds for the disadvantages of computer modeling:

• About “unreality” of the computer objects: there are thousands of photos of plastic and cartoon models, on the Internet. Their authors proudly presents their masterpieces, originated from the standard kits. They show it this way to the worldwide audience. Without such information channel, the existence of their work would be known only to a few colleagues, who have occasion to see it in the reality. Look at this site – I have also presented my model, using pictures. Tell me, is there any difference in the medium? No! We all communicate with the outer world with the images of our airplanes. For the potential audience, the classic models, and the computer models, are on the same level of the "reality": the reality of a picture.
  Instead of checking the model "by touch", you can see all the small irregularites of its surfaces on the screen. Assign to the model's surfaces a kind of a silver-gray, specular color. (It is just for the time of shaping, only. It will be changed later). When you examine such surfaces against the light source, you will easily find even very small differences from proper shape.
  (Note about technical solutions of the "touching problem": I do not think, that something will change in the nearest future. To touch an object created in the computer, you need two things: force-feedback pointing device, and software with user interface adapted to it. No data glove manipulator has real force feedback – an mechanic device that would produce enough force was not invented, yet. There are on the market some force feedback manipulators. A popular one – named “Phantom” – is in fact a device that represents a single "contact point". It has maximum force resistance less than 100 N. To use it with full realism, a 3D program should deliver it the information about forces at actual space location. This way the user would feel a friction of the coarse painted surface, or smoothness of the glass. Today no widely used program has architecture suited for this purpose – at least I have not know about any. What’s more important, it seems that the development of force-feedback devices is rather slow. I remember, that in 1996 I collected information about the “virtual reality” input and output devices, especially the force feedback manipulators. Do you believe, that after 10 years, in 2006, I have found the same devices, produced by the same companies? And there are only a very few 3D modeling programs, adapted to these pointers!)
• About the substitute of a "model kit" in 3D graphics: I think, that there is simple solution for the lack of available models: share your airplanes with the others! In the world of computer files, when you give a copy of your model to another hobbyist, you loose nothing. The potential commercial use of your work, and its immutability, may be safeguarded by a kind of license (for example – CC license, or similar), placed in the model. Well, I know that it s not enough for a malicious one, who would rebuild your model, and sell it as his own work. However, it seems to me that we often overestimate the chance of such a situation. Notice, that the free software phenomena become possible when the programmers stopped to think that way. Why not to start similar thing with the 3D models? The computer program is a thing that enables you to produce a document, or calculate something. The model is a thing, that enables you to create an interesting picture, or an animation. So I have decided "to be in the first row" – and publish my airplanes for non-commercial use.
  (Note: two years later, on 2009, some other sites have also opened their archives - for example Anders Lejczak site. An interesting story has happened to his Spitfire V model. It was painted as the Polish ace, Jan Zumbach's plane, from Sq 303. On 2009 the radical British National Party (BNP) has used it, without Author's permission and knowledge, as the main picture of their political campaign. As you can expect from the radical nationalists, it was an anti-immigration campaign, called "Battle Of Britain 2009". These radicals were not smart guys, and used this model "as it is". So the plane of the immigrant pilot, one of "the few" who saved Great Britain on 1940, proundly flies as the logo of anti-immigrant campaign. BNP even did not remove the Polish national insignia - "checkboard" - from the engine cowling. If you check a little the "Battle of Britain" story, it can be conluded that the such "immigrant pilots" - Czech and Polish - were the "fresh replacements", thrown into the battle at is climax. It is possible, that RAF would not win this campaign, without their support. )
• Last disadvantage - the time spent to create computer model: Well, I cannot propose any special workaround. I try to give you some hints in the guide. Your second model should take less time than the first one, anyway.