The idea of providing modular parts is pretty nifty, and the set provides ample pieces to build your fleet with. While I like the thing a lot, and definitely recommend it, there are a few criticisms:

For one, the pieces are overly fiddly. The glue flaps are tiny, and some of the boxes would profit from different cut/glue lines.

Second, there's no alternate color scheme. If you want to create different factions (and you do), it's difficult to build visually distinct fleets. I'll probably use decals. Unfortunately, you can't even use Photoshop to tweak the colors, as the file is protected.

Finally, the textures might be a bit dated, compated to current papercraft standards. But that'a really minor point.

Again, this is a good product, worth the money. It just could be even better!

The T-Builder is quite easy to use, it's just a matter of clicking on the options in the layered pdf menu. The graphics are pretty good, though somewhat in favour of a Diablo-style fantasy game (not too much scifi specific content). This doesn't matter much, as the vast majority of the graphics is universally useful and useable. All in all, the product is well worth the price, and I have no serious criticisms.