After doing a little bit of googling, I assume the tune 4 is also "race 97" which is supposed to be for induction kits and run on high octane fuel. Also, you will very rarely see a power increase from a bluefin install. Seems to be just for reliabilty/response etc. the car will "go" better, but wont have anymore power. Well, so say the many reviews I've stumbled across.

I would go for the RR treatment and see what comes up.

My RS turbo seemed a bit lacking in power when I first bought it. Turns out it had a weak actuator and was holding no boost! Made 99bhp! I would have never guessed it was missing that many ponies.