I wonder this myself. Maybe in Japan or Canada it would be a respectable choice, but I only know one person who had a Skyline IRL, and besides it's sex appeal, it really didn't impress anyone.
The person I knew owned a card shop. He was making okay money, but his wife was raking in the cash. He sold his late father's vette and managed to import a Skyline R33 GTR a month or two later. I never knew the year and I don't even know when the R34 came out, but I'm sure it's a R33 and I think it was a '96 spec. To get to the point, it was obviously badass to know someone with a skyline, but that car really couldn't hold it's own against much more than a 350Z, S2k or Mustang GT. He ended up haveing some sort of problem where he couldn't end up getting enough oil in the crak or whatever crazy story he came up with and the engine blew on him, but I just remeber a few weeks prior when we were in his $30-40k+ imported Skyline seeing a LS1 Trans Am pull out of the local car deal and merge into traffic ahead of us. They met up at the next stoplight and it was sort of sad. This Trans am was obviously stock and was being driven by what looked to be a car salesman. He blew the doors off of the GTR.
Anyway, I guess the way people build up these cars just makes it hurt more when they lose. I guess the the top model R34 would be no more than in the mid to low 13 second 1/4 mile range? I just can't see him beating a US spec Impreza STi or EVO.
Btw, the only mod done to the Skyline was a full exhaust from the downpipe back. It was custom made, since the card shop owner was pretty good with exhaust work. That was the only mod done to the vette his father owned, as well.
The point I tried but probably failed to make is if you get past the initial 'omg skyline' part, it really is just a sporty car, with a plain interior, and okay performance stock. I would get rid of the MR2 and go for the best deal you can get wherever you live, whether it be mustang or WRX. But I just don't really think a Skyline is all that much of a choice if you live in a place where you need it imported. If you live in Japan or Europe, then that's a different story.
With all that aside, I'd trade my left nut for an R34 GTR. I really don't need two of them.
EDIT: Yeah, he ended up selling the car 'as is' to some young guy after the engine blew, never to see it again. He drives a VW Passat now.:/