Regular Microwaves vs RV Microwaves

My RV microwave does have a venting system. Since the turntable has died, I will be replacing it with something from Walmart that most nearly fits the space. I may get a Panasonic because that make uses inverter technology so running at lower power doesn't "pulse" on and off, it actually consumes less power when set to 80% or 40%.

If I can't find one to fit--then I'll buy the cheapest one that does fit.