Acceleration comprimise?

Anyone who installs clutches-etc?, who can tell me if a slip release bearing is on the way out is accel affected a new clutch un-avoidable?. Just checked serv hist and am astonished recon g-b a helix organic fitted 29'000miles ago costing £1440! lol, geez was ripped a did'nt get a L/W flywheel fitted whilst paying £925lab!!!. Hope bearing can do 2000+miles?. Sorry to ramble!!!.