Thanks for the feedback. I have to admit that my first reaction was to go with the Super Platter since it seems to be "the upgrade" and it would also allow me to use the P-ring.
Then I started considering a few other things.
The Aries I has an incredible reputation. Could its platter sound just as good or better than one of these other platters even with just a standard bearing? Maybe someone can answer this question for me. What type of bearing is used in the Aries I table with its stock platter? Standard or Inverted?
It also occurred to me that the 12" platters might require that I remove the cover from the motor pulley permanently. It definitely requires a different pulley. After I measured the stock platter and clearence it seemed like it might fit after all. However, once I considered the added diameter of a P-ring it seemed to me that the cover would have to go without a doubt.
I have actually read that some people remove the cover purposely, and they have stated it has a positive affect on the sound of the table. I don't know about that, I have played it both ways and can't discern a difference. Being able to leave the cover in place is simply an aesthetic preference on my part, if someone told me that getting the 12" platters required its removal but the sonic improvement over the Aries I platter would blow me away I would remove it, otherwise I would prefer to leave it alone.