By the way, have ordered the K&N off ebay (£45 inc delivery).
Decided to go for that in the end because i've had K&N in my last 3 or 4 cars and they have always given good results, especially on turbocharged engines.
Will let you know how I get on. I am sure it will help, it's currently still running on the factory fitted filter so it's got 40K's worth of crap in there.