Are those carbon fiber? Or just covered in a carbon fiber look material? I think they should look pretty good on white.

I would not believe them to be full carbon fiber. I don't know much about the rims available out there, but the hub where the bolts are is aluminium. Will he guarantee them not to be warped?

Check around like Tirerack http://www.tirerack.com/wheels/results.jsp?autoMake=Scion&autoModel=xB&autoYear=2008&autoModClar=

Good luck

PS another thread here shows tirerack link to support the website.
http://newscionxb.com/wheels_tires/attn_tirerack_shoppers-t22.0.html

Update: Carbon Fiber rims I've found have had a magneisum or aluminium inserts attached to the insides. I can't judge by the pictures well enough to say they are not carbon fiber.  Examples I've found (motorcycle rims here ) http://www.blackstonetek.com/announcing1.htm

Doesnt look to be real CF, I love CF and there really isnt that many manufacturers that offer real CF wheels. CF is a pretty expensive material, especially if the wheel is all CF, it would cost quite a bit and I dont think the guy would let them go for 800. More like 800 each haha. I mean the Volk magnesium wheels, used run about 1200 each, CF should be even lighter. I researched it before, on a few companies recently came out with read CF overlay on the wheels, and those run anywhere from $800-1500 each! From what I can tell, it looks like its the CF vinyl wrapped wheel or just painted on pattern.

One thing I notice, a lot of the wheels that are 19s but with the curve spokes, it makes the wheel look much smaller. Like with my TRDs, people have asked if they were 17s or 18s because of how the wheel curves in. If I went with a flat spoked wheel, it would look much larger. This wheel has the curved spokes too so it would have the same effect of appearing smaller. My 2 cents.

Nah, those falken's you posted in the box are sweet, hope those are the ones you went with.