My wife has a 2004 G35 6MT coupe. I've got a 2000 986 S. The G35 is a nice car, but it's no Porsche (Boxster or otherwise). The get-up-and-go is there, and it looks fine, but the build quality just ain't the same.
She's got a creak/pop coming from the rear of the car that Infinity has a TSB for. The dealer has had the car twice and can't solve the problem. On top of that, bits in the interior that are painted plastic that I know will delaminate eventually. I guess the soft-touch Porsche interior is kind of like this, but not really. I like her car, and I'm glad she's got it. It's nice to have something like that with a trunk and plenty of cargo space, but she'll NEVER keep up in the twisties!