I can honestly say that of the 3 cars (350Z, Boxster, TT) I find myself instinctively drawn to the 350Z the most. It's just a bit more less..... well, German. I've always liked cars that are a bit rough around the edges (previously owned an Elise, a VX220, a couple of modified Minis, and a modifed E30 BMW) and the 350Z appeals to that side of me quite a lot.
Even the girlfriend likes the Zed more which is surprising as it's the least subtle of the three, and she tends to go for understated more than brash.