Resetting the ECU has solved the problem
The car now revs freely round to 7k as it did before, but seems to breathe better through the whole rev range which is exactly what i was expecting from the new exhaust. So i'm happy.
Wasn't expecting any major changes so was suprised the car behaved as it did. If anything i'd say that before the ECU reset the car performed as if the timing was advanced by couple of degrees, lots of power at low revs but struggling at higher revs. And a slightly high idle speed.
Still got a slight rattle going from 6-7k but nowhere near as bad as before, will follow your advice to figure it out Taz.
Fade, i agree about the BHP turning heads thing, although the noise from pipes where two silencers should be also turns heads
I was expecting to get what you described but ended up getting more power low down and less higher up.
I had the exhaust fitted now without any other mods as the last exhaust needed replacing for the MOT, so it's in preparation for more engine mods at a later stage. Will definately be getting a new air filter and chip, but trying to work out whether to go for more serious mods as well or just put the money towards a Scooby. Modding the engine is a slippery (and expensive) slope...
Handy to know the fuel pump is ok up to 170bhp, i'm hoping that if i just add a filter/chip nothing else will need uprating.
But before all that... i'm gonna play with the handling