AT-OC9ML/II vs. Shelter 501 Mk2 using the JMW9

I currently own the AT-OC9ML/II and was looking to upgrade my cart. Has anybody had the chance to compare these 2 carts on a VPI Scout with a JMW9 arm ? Is the Shelter 501 Mk2 a worthy upgrade or do I have to dig much deeper to find a suitable replacement for the AT-OC9ML/II ?

BTW, they are plugged to a Monolithic PS-1 and HC-1b with the ModWright upgrade mod.
Thanks !
In the Audio Asylum there is a owner ( John Elliot ) who owns that AT OC9 and when I remember right, he says, that is is a real good cartridge.
When he is right, then you have to go a bigger step forward, when not, then there are very much choices out there .....anyway probably Shelter 90X.
I still use an OC9 but also have a denon 304 as backup. They are used in an alphason arm on a roxan zerxes deck. Both cartidges have thier strengths. I believe I may prefer the denon but I would have to go back to remount it to confirm this....still the OC9 is a fine cartidge. I would run it until retipping and look for that last great cartidge...have fun,...
Just a heads up - you will be a little short on gain with the PS-1. I think the max is 53bB, where the .4mV Shelter would probably match up better with something around 60bB.

I am using the Dynavector 20XH with the Scout/JWM9, but I have shortlisted the Lyra Dorian, Sumiko Blackbird and Dynavector Katat D2 Mk. II for my next upgrade, along with the Shelter.