While I had one fail at about 2000 miles, normally the spigot bush will safely do the life of at least two clutches. But it is a very cheap component, whose replacement takes the same labour as a clutch replacement, so any doubt, do it!
Failure of mine was total, one piece crank and gear-box input shaft and with the engine running, you could not select any gear. Got about 200 miles warning but didn't know what it was. All worked, but holding the clutch pedal down produced a rustling sound like dry leaves were being stirred.
