If at all possible, try to get samples from the printers you are interested in. Companies that don't supply them would make me wonder what they are trying to hide. I've gotten a sample from one printer company and another is on the way.
I'm not sure you really want to rely on photos anyway. I just took some DLSR photos of a couple print samples I got and it was very hard to show the actual detail of the layers. These were white samples, though, and darker colors would probably photograph a lot better.
Also, most 3D print manufacturers seem to have forums with print galleries where owners show off their creations. Perhaps 3DS does as well.
Mike
