How many hours can benz glyder cartridge last till

How long can a phono cartridge last till it needs re-tipped?.
assuming it has been set up properly, I am looking to buy a cartridge, with 300 hours , is it still going to give say 75% good sound quailty ?

Please give me feedback.
It should give near 95% of the sound QUALITY and have another 700-1000 hours of life left if set-up correctly . A cartridge will actually sound better after the first 100 hours and have a very slow degrading [ maybe 2% or less per 100 hours IMHO ] of sound .