The 997TT is very good. However, like many other new cars here a ridiculous price. If I lived somewhere else and had the money I would consider it. Even if I could, I wouldn't buy it here.
For half the price you can put an X51 motor, tranny and real suspension/brakes in a Cayman. That is very very good. Even a tweaked Cayaman S is very good. Not as lush, but then the 997TT is far from dramatic.
The Cayman is a damn nice car, not as iconic as the 911 but I wouldn't say no. Certainly a lot better looking, and less common, than the Boxster. I considered the latter for a while, but those are soooo common, plus they're a convertible which I don't want as long as I live in the UK, and even the 3.2 S isn't that fast (I managed to get by one in my 840, and he was trying, though well into triple figures on an airstrip of course) so that's pretty well ruled out. Loads cheaper though, good 986 3.2 S go for £15-20k depending on age & mileage.
I agree the 911 TT is far from a thoroughbred sports car (that's what the GT3, or even the GT3 RS, is for) but that's a compromise I'd be more than willing to make. It's still quicker than most things, handles damn well, yet can be driven across Europe in comfort. The GT3 and the like are just a little too raw, it'd become a weekend car. Saying that I can't afford either so it's a moot point

.