I've had two amps with provision to switch to triode, a VAC Phi 110 and a Cary 120S. In both cases, triode operation was less than satisfactory, no dynamics, lack of detail, and limited frequency response. My speakers are designed for tubes.
However an amp designed as a triode, BAT VK55 in my case is preferable to the other amps I've had that were ultralinear AB amps.
So, don't get mislead into believing you will get true triode sound in an amp that offers that with the flick of a switch.
I have no experience with the Cary V12 so I can't say that it would better your M60's.