Medici, good to know that I was missed! I was off line for sometimes as I was busy moving office. I was also assisting my partner in a murder trial!
Single vs twin. That's a conundrum! I am advised by the HKS guy over here that the single has less lag than twin. (although that seems to defy logic! I mean, it takes a hell of a lot more to move a huge single than a pair of small turbos. But I suppose in a twin configuration, the exhaust gas would be divided to turn a pair of turbo while in a single set up the whole gas turn a single turbo - that balances it out I suppose).
I know however that many draggers use singles. Single also reduces weight as there is only one turbo and one everything else. I am also advised by this guy that a TT would be better around the track than a single as the TT top end is almost inevitably better . I tend to agree with that because on the track, after the TO4R guy overtook me in 2nd, I managed to catch up when my boost came on full (bearing in mind I was in 3rd when he overtook me). I however could not overtake him the lap after that because his suspensions is better set up (he uses 2 spring set up at the rear) and his AP caliper is far better than mind (full racing caliper compared to my road and track caliper). But on fast corners, I always caught up with him. I think my TT and cam set up is better than his on the track (anyway my car is optimised for track). The TO4R I think behaves more like the GT2530s (which I am advised is the best TT set up up to 550 hp).
So it boils down to preference and driving condition really. Having a GTR is half the fun ....the other half is getting to know the beast and setting it up to your own requirement. I am pleased to learn that you will be owning one soon. I tell ya....you won't regret it!