The basic options are
stock - dual mass flywheel, p/p, friction disk & hardware
singlemass f/w either 993RS M003 or aftermarket + stock as above
either of the above flywheels w/ centerforce or other aftermarket p/p & f/d
options here
most people like the single mass RS/CS M003 singlemass f/w, the downside is some extra gear rattle at idle. I would use the stock 993tt f/d & p/p w/ the RS/CS singlemass f/w but the centerforce is nice too