Rotating Carts

I have gone the three arm (one with a removable headshell) route. My best cartridge, Hyperion MR, is a permanent resident on my best arm, the second fixed headshell arm has an excellent Hana Red that is my current go to stereo cartridge while my Myajima Zero currently is on the SME 3012r arm with intechangable headshells.  I can swap in a Kleos, upgraded Denon103r, or Andante P78 all mounted on their own headshells for fun.  Each cartridge has a counter to remind me to enjoy all of them and not put too many hours on a single one.  I am very adept at cartridge setup, but the ultimate fine tuning requires time and I prefer to enjoy the music as opposed to a lot of fiddling constant changes could require once the final adjustments are made.

Not sure how much real difference that would make. I have a dozen MC carts and use primarily my favorite; seldom rotate other carts in and out. 

I wanted and finally got complete flexibility with 3 arms, all removable headshells. The more flexibility, the easier it is to listen to my small collection, and have friends bring their cartridges, and my spinner maintains speed even if all 3 arms are in the grooves, so comparing in seconds is just a matter of rotating the selector A,B,C on my SUT, 

latest, 3 removable headshells

prior, only 1 removable headshell

For me, the ease of change is far more important than the 'idea' of fixed or longer being better.

You need one of those wristwatch rotators. 

I rotate to keep my Carts near the same hours.