Hey. So the Evo MR I had (with the dual clutch transmission) gave me more confidence when driving and turning fast compared to my Z, just because of its all wheel drive, but that doesn't mean it was any faster. Unfortunately the dual clutch sucked and was the reason I traded it in for the Z. The clutch plates kept slipping and I knew the problems would only get worse in the future. The GSR model only has 5 gears which IMO is 1 gear to little. The Z is more fun to drive and looks way sexier. However, if your friend likes to go off roading, there is nothing more fun than an Evo with some proper tires on dirt or snow. I will say though, that if my dual clutch wasn't giving me problems, I would have stuck with the Evo, but if my Z got totaled today, I most likely wouldn't get the Evo. Hope that helps.
about purchasing wheels and tires in winter being cheaper...not necessarily. It all depends on the type of wheels as some are special order types. Volk Rays are always up there so you just have to shop around for a good deal. If you can find someone selling theirs you can save the most. Tires are a different story, just wait for them to go on sale.