I have a 50 amp coach and will tell you what I have done (2 A/C's)
I did not buy the
Power Solutions product as I felt that I could "Home brew" one for less. So I did. basically an identical device only built by me not them at a much lower price.
The campsite I'm on just now is 50 amp, no problem Everything works exactly as designed at the factory
The campsite I was on last time (next door to where I am now) is 30 amp.. I opened the box. pulled the plug and socket apart, grabbed the Heavy Duty extension, plugged it into the 20 amp outlet next to the 30 in the box. and everything worked, Much the same as it is now. Just wife had to be a bit careful of turning on too many things on the (Water heater, Microwave and 1 A/c will trip 30 amps)
The thing works very well and I recommend it.
Only problem is: One chain of parks I stay at they are disabling the 20 amp outlets. (Simply to make sure you can't do what we do here)