Before I got my BMW 335d I was looking at these and saw that with stage too you wont get much beyond 400bhp without spending some £££.You won't regret it. It's the next level up from Stage 2+ 2.0TFSI's I'd say but being RWD it's much more fun (dangerous ). Stage 1 remap puts it past Stage2+ K1's etc at around 380bhp, Stage 2+ is around 440bhp.
I guess the next level up from this, if you want to buy off the shelf cars would be Porsche 911 Turbo or GTR I guess...where do you really go after that?
Exhaust, Meth, intake, intercooler to get anywhere near 440bhp.
STILL Stage 1-2 power without doing much is pretty awesome and mental power