Agreed codex, it's getting difficult to tell a render apart from the real thing. However, the google translation of his page seems to indicate he did in fact construct the model. Seems kind of pointless to lie to the interwebz at large. I've seen various other gundam models built to such a degree of efficacy. Another of the reasons they look so good is because of the use of colored cardstock as opposed to printing the colors onto white cardstock. Just check out this guy:
Gudang Papercraft Ardi: Super Gundam Papercraft
Papmod | Papercraft | Paper Model | Card Model
Gundams lend themselves to looking good on paper (bit of a pun there) because of the straight planar surfaces and simply curved surfaces. Moreso, I just meant to highlight the tight, closed, and neat seams. I'm sure being able to use a ruler to make the cuts as opposed to freehanding a curve plays a critical step in that. When I design a model it looks great (at least in my humble opinion), but when I build it, I'm always a bit disappointed with my skills. Obviously I allow for the fact that the real version will never look quite like the designed version. I just know I can make my real version better and want to try. Just not always sure how, I'd love to watch a YouTube video of one of these pro guys cutting/building just to get an idea of what they do or don't do.
Nice render btw, what software?