I have no idea on how long the suspension lasts, but, on my Sansui turntable, it has what looks to be the original 27 year old Sansui cartridge that sounds OK. Not like my Symphonic Line RG8 mind you (modded Van Den Hul Grasshopper), but not terrible.
Also, so there is no misunderstanding rebuilt is different then used.
To your question, I would be a bit leary of buying a used cartridge only because you never know what you are getting.