"are these hubcentric? if not, are the hub rings included?"
I'm not sure though i will be sure to check with Enkei tommorow and post the answer.
"how about caliper clearance? what are the brakes that it will or will not clear?"
Should clear all stock impreza calipers including WRX, Enkei couldn't give me a clear answer on STi brakes so we have a set comming to test fit onto an STi i'm hoping that by early next week i will be able to tell you for sure.
how about lugnuts?
Theses rims work just fine on stock lugs though i can supply socket lugs, or lighweight lugs for rays, i will post pricing on optional lug stuff very soon.
awesome pricing btw!! glad you think so! i though so too!
thanks for the q's i will be posting more answers as soon as i have them