Hi mate, Welcome to the club
To be honest mate. I have had my n/a supe now for 2 months. and touch wood i have had no problems. Now me personally I'd go for looks rather than speed. Your only talking a couple of seconds at the most if you got a tt. The n/a can hold its own on the road and looks the dogs bollocks.
So if your talking money wise then you should go for the n/a. Ok who wouldn't mind having a tt than a n/a. But you have to ask your self "are you going to be racing it everywhere"
you could pick a decent tt up for about £8000-£9000
or you could go for the n/a for about £4000-£6000
its a lot of money if you ask me, not to mention you'd have a lot more to go wrong with a tt.
but that's just my opinion.