I do enjoy other amps weather I own them or not but I can’t say I get tired of the Mark IV. There is just too much to do with that amp, but I hear you! And that’s why I always have different sets of power tubes around but I usually float back and forth between 4x6L6 and the 2xEL34/6L6.
Can’t say I get tired of one combination and go to the other, just started craving the other.