My '05 Forester XT has the UK model 2.0 Turbo and I need advice on the best modification path for this engine.

I know about PPP but would prefer something that allows a second stage of tuning without replacing what's already fitted.

So, the stock 2.0 litre delivers 177ps / 245nm.

I believe the '05 WRX 2.0 litre delivers 225ps / 300nm.

Is there a commonly accepted route to say:

a) stage 1 at about 225ps
b) stage 2 at ????

Is Ecutek + exhaust going to do it or is it cheaper to do Ecutek & S/H turbo?

Any info gratefully received.

Ian