daveyf,
It took average 1 cartridge per week to record this observation for 12 years. Maybe 1 minute a week or so. Get the calculator and check.
This is my personal guide when buying and selling cartridges. Don't make any other assumptions.
I know if I have trade in old $300 Grado Platinum, I can easy sell it later for $150 that is roughly 50% of original cost. Your old $4000 Benz Ruby 2 will be good sell if you get 25% for it in any condition. As far as I remember you had hard time to sell yours Ruby-2 at $800 just few month ago.. it is strictly about re-sale technical grade.
Please read what's written including explanation. If you don't like my technical grading or sonic grading- you can offer your own.
May be it will be based on color, material, price or something else. Audiogon welcomes any ideas that based on experience.
My bias is ranked from 1 to 500 if that's what you mean to say. Also being biased I would make no sense by buying #415 GAS Sleeping Beauty in any quantity ahead of single #7 Symphonic Line RG-8L ; based on fact that I can sell GAS with turbo speed and need to wait years to find a single buyer for RG-8L