Comparing pics of the 1:1 and the kit, the wheels do look undersized even if it's just an illusion. Somehow I think Fujimi's pulling another fast one, making both kits with 17's and marketing the IS 350 as if it has 18's.
There's only one way to find out, when the kit comes out someone can take calipers to the wheels and tell us what diameter they are. If they are correct in diameter, they'll be about .80' - .82" in diameter, if they're really 17's masquerading as 18's then they'll be about .75" diameter.
Fujimi calls the Lamborghini Gallardo Sportecs 19", but they scale out as 18's
Glad I didn't buy any. Nothing worse than undersized wheels.