In my experience, yes, Menzerna polishes do take a while to break down with an orbital (this is true of a number of "diminishing abrasive" polishes, not confined to just Menzerna). I've managed to damage a pad or three working the UDM at high speed for long times. My solution: Multiple pads, and at least one extra backing plate. The fast change of direction of the UDM orbit generates a good amount of heat in the hook-and-loop fabric. The backing plate will act as a heat sink and soak up some of that heat for a while, but once it gets hot enough, the pad backing and foam start taking damage from the heat (and some polishes start to act strange when the pad warms up).
To prevent heat-related problems, I switch pads after every few panels, and keep checking the backing plate for heat build-up. If the plate gets too hot, I swap it out, too.
I'm sure others can offer more Menzerna-specific advice (my experiences are with Power Gloss Intensive Polish, Final Polish II, and the Blackfire "scratch resistant" compounds), but as for the heat problem, that's how I've dealt with it.
Good luck,
Tort