GIGABYTE GeForce GTX 470s are fine, the major difference between them and XFX is customer support and warranty. Besides, XFX don't even make GTX 480s/GTX 470s, they were 'banned' from doing so. SAPPHIRE makes ATi cards only.
Gigabyte is a very good brand for PC parts. Their video cards in the GTX 470 lineup right now are just Reference cards, as PsychoSaysDie indicated. Basically, just about everyone selling the GTX 470 right now is selling nVidia's release version with their own stickers on them.
Only way to get different is to go with Palit or someone who has already put their own cooler/fan on it. Otherwise it's all the same parts.