As mentioned above, despite the apparent advantage of lower output MC much will depend on you phonostage gain and noise and where is runs optimally. By the way, what phono amp are you considering?
As far as high end MM cartridges go: I don't see how a phonostage by TRL could impact the decision MM vs. MC. There are many excellent phonostages for MC out there and together with added advantage of MC, the choice for high end would seem always an MC cartridge. Aside from the Decca and some high output MC, I can only name the Music Man MM cartridges that are supposed to be playing in the higher leagues.
As far as high end MM cartridges go: I don't see how a phonostage by TRL could impact the decision MM vs. MC. There are many excellent phonostages for MC out there and together with added advantage of MC, the choice for high end would seem always an MC cartridge. Aside from the Decca and some high output MC, I can only name the Music Man MM cartridges that are supposed to be playing in the higher leagues.