I put one of the Splendide "combination" washer/dryers in my last bus. It was a $1400 unit that I bought with a cosmetic blemish for $900. It did not perform well and after less than six months I took it out and put a for sale sign on it. Two years later I hauled it to the dump.....
My current travel trailer has an "apartment style" stacking washer/dryer (120v dryer). They work fine however..... As sparing as I can possibly be with laundry the washer still accounts for 50% of our water consumption. As we rely on rainwater collection here for domestic water that consumption is a big deal.
It is VERY unlikely that I will put one in my next rig.
If you decide to put one in and plan on any boondocking be sure and look VERY close at water usage.
Not quite what you were asking about but I know some folks that use this manual machine on their sailboat and love it: https://www.amazon.com/Laundry-Alter...=wonder+washer