[DanEC]

Mis-alignment does seem to be a common enemy of these hydraulic cylinders. One of my brake masters leaked almost immediately upon getting it on the road and I found the bore scraped up where the piston had been rubbing on it. It's kind of hard to get a good alignment on the clutch slave because the fork moves in an arc as it's depressed - especially if the rod is fairly short. About all that can be done is to try to shim and center it as much as possible.