My guess is the bolt pattern is the same, but personally I'd get some aftermarket wheels simply because factory ones tend to be much heavier...that is, tend to be, not sure what the spec v wheels weigh but they do look nice
The B15 will not fit regardless of what anyone said. ours B13-14 were 4X100, these new shits fit straight into the Altima, what a suck ass design. And yes they are heavier, very easily bend, the Spec V.
Go to www.discounttiredirect.com and go to the wheel section. Some of the ATS wheels (Saturn or Mira) on that site resemble the Spec V rims...at least I think so. Not to mention you'll get a better deal on the ATS's.