Sadowsky5, i have got 3600K's on my XR6 Ute and so far i have loved everything about it. The power is ok for me as previous rides were all diesel 4x4's lol So far heaps of other young blokes in various types of car have pulled along side me, done the "oh, its not the turbo" look and i have been able to teach most a lesson!
I chose the SSS box and i love it now that i have given it a workout, it really is good fun, and when i get tired of it.... i just slot it back in "D" and cruise.
Definately get the LSD option, its worth its weight in gold

Another option i recommend is the leather seats... very comfortable and i do love mine. Basically if its a present (how good is that by the way!) get every option you can such as the 18" rims.... they look hot.
The cabin tidy is also very handy but if your like me and think that space suits subs better, then dont get it
Anyway, basically option anything you can. I havent had a problem with mine except trying to keep it clean (bloody weather... and work)
All the best mate,
Matt