I bought a reverb from here and even on the fastest setting it is deadly slow at returning to full height. The guy I bought it from told me (after he'd posted it) if you over-tighten the seatclamp it prevents the seat returning to the normal height at all, however, if I don't tighten it enough the post slips down the frame. I have found a balance between tightness of clamp and speed of return but it is deadly slow.
Is this a common problem? Would you accept this?