These units are not made specifically for RV's. They are popular outside
the US in countries where floor space is at a premium, and water,
electricity and detergent are expensive.
The vented units are cheaper and cost less to run, plus are less
complicated than the condensing models. Condensing models are for
installations where outside venting is not practical. They use cold water
to chill the dryer exhaust and condense the moisture coming out of the
clothes, then it goes down the drain. In RV installations unless you are
extremely averse to making a vent (it can be through the floor so it
doesn't show outside) the vented models are preferable.
The pluses are:
Use little water - not of much concern if you are in a flat rate park
Use little electricity - not of much concern if you are in a flat rate
park
Use little detergent as compared with top loader washers
Take up less floor space than separate washer-dryer sets
Take up less overhead space than stacked washer-dryer sets, though as the
combos are front loaders you may want to install it on a pedestal to keep
from having to bend over so far. The pedestal can have a drawer or
cabinet in it.
Weigh less than separate or stacked washer-dryer sets
Minuses:
Expensive compared to separate or stacked washer-dryer sets. However
floor space in RVs is at a premium, so the extra expense can easily be
worth it.
Can do only one load at a time (cannot have a second wash load going
while drying the first wash load)
Relatively small dryer capacity since the same drum is used for drying as
for washing
Not distributed like major brand conventional washers and dryers, so
service can be a problem if you have a breakdown far from a service
provider
You can do a lot of washloads in park laundromats for what one of these
things costs, plus the laundromat doesn't take up any space in your RV.
And if the laundromat machine breaks down, it isn't your problem.
Al