Last week happily bombing along at 70MPH on the freeway the car seemed to stutter a bit but then clear itself, but later that day it started to **** me off as it wouldn't rev past 2000 RPM and eventually 1500, I checked air pipes, cleaned the induction filter but still same so I gathered it must be a fuel starvation issue, tried running it without the gas cap incase it had a blocked breather but same ****.
Drained the sedimenter and all was clean, no bits, no water. Changed fuel filter as for the sake of 8GBP may as well, no joy.
Tried priming system but no resistance on lever.
Removed fuel inlet and outlet pipes on lift pump and had someone crank car over but no vacuum or outlet so figured lift pump to be fubar..
Bought a decent replacement a Delphi one, changed it all by myself, took care to fit right and car still run like crap.
Removed fuel lines again and blew thru pipe from tank, either it had a partial blockage or somehow an airlock?! Was hard to blow thru at first but seemed to clear after a second or so.
Reconnected and fired it up and took it for a drive. All working perfectly!

Old lift pump DEFINATELY was shagged no doubt, not sure why new one didn't fix it immediately but working sweet now.

Moral is, if its not in the fuel filter or the sedimenter then the lift pump is most likely the cause. And buy Delphi their parts are brilliant!