Sorry, I guess my post didn't come across very well. I don't think they're bad at all: I think there's bits of them I don't like, but then that's the same for every car. Our long-term plan is to replace my 911 with a 350Z and swap Jo's Scooby out for a GTR in a couple of years time, so assuming that comes to fruition then I'll be more than happy to drive one. That's her car though, and I just can't get past the Lego-brick looks (and that's coming from a VXR220 owner!) and the poor quality materials inside. They also don't feel as superquick as the figures imply for some reason, or at least the MY09 cars didn't. I guess having 1800kg to move can do that, and I'm finding myself preferring stuff that's lighter weight to behemoths with monster power.
Never having owned either I suspect this next comment is going to seem a bit odd, but I suspect that owning a GTR will never give you the same buzz that you get from starting up the Aston or Ferrari and popping down to the shops. Much, much quicker than either, but less of an event which is what I'd want.