I was looking at those too - seems DAMN cheap... $125 per rim... I dunno - I haven't seen anything about this company...
I'm getting a set for a few hundred more, but better tires (the ones they offer are chinese shit at that price) and I'm having the TPMS sensors moved over too, so it's like mounting and dismounting another set of tires.
Plus I know the vendor well and know that he doesn't import shitty rims that will crack, etc.
EDIT: And I'm getting 235 40 18's... not 225...
2007 Z4 3.0si