Even in rural Texas, I am seeing ProMasters available for sale and being serviced, so the days of trying to find a Five Star Dodge dealer are gone. FCA (Fiat-Chrysler Autos) seems to be doubling down on the PM in the US, so my confidence on finding parts or service if broken down is high.
The Rialta would be hard to recreate, as a lot of it depends on the VW chassis, which hasn't been seen in the US since 2005. I'd say the Travato is a unit like the Rialta in many ways, even bringing some of the Rialta's quirks as well (the sump pump for the shower pan for example.)
The Trend, OTOH, is a different ballgame. I think it will attract the same cult following as the Rialta, but it doesn't have as many annoying quirks as the Travato. It is a foot fatter, taller, and two feet wider than the Travato, but it isn't huge.
So far, here are a list of things I've read about that are notable about the Trend:
1: The water heater appears to be a Girard heater. You use this somewhat opposite of how you use a normal tank heater. To lower the temperature of the water, you turn the hot water on more, turn the dial on the water heater control lower, or slowly add cold water. Oddball, but for unlimited length hot showers, not a bad trade-off in such a small rig. Beats trying to go into a bath-house where the stuff on the floor starts trying to eat your shower shoes.
2: The drop-down bed. It supports max 450 pounds. The 23B floor plan, you will get acquainted with this bed rather well (it is pretty much a couple inches short of a full queen in both dimensions). Make sure to knock over the seat cushions that are upright before dropping the bed. The 23L has a rear quarter bed... not really queen size, but large enough for two people. With the 23L floorplan, the drop down bed isn't really needed, but it is useful in a pinch to sleep that friend or family member, and is about 3/5 the size of the one in the 23B layout.
3: The generator is a 2800 watt model. It will start the 13.5k BTU/hr A/C with 300 watts to spare (as per Onan's documentation), but you are not going to be running the microwave or even the Keurig coffee maker with the compressor at full tilt.
4: The furnace has a thermostat, but the A/C has separate controls, which are located on the lower part of the unit on the ceiling. Another trade-off (since most "C"s tend to have a single thermostat for heat and A/C these days), but not a deal-killer unless one is too short to reach them, or has range of motion issues with the shoulder.
5: The propane tank is 13 gallons. With overhead for vapor, that is about ten gallons. I highly recommend an Extend-A-Stay unit be installed with this rig, so one can bring a couple 20# bottles on a hitch mounted rack.
6: With a 24 gallon fuel tank, you have 18 gallons of gas for the generator (the last 1/4 will be reserved for the engine), and at the genset running full tilt, that is 36 hours of use... to 72 hours, if the generator is only lightly loaded. One can always use a hitch mounted rack with five gallon fuel cans to extend this if needed.
7: The 23L floorplan has more outside storage by almost a factor of two than the 23B, due to the space taken up by the corner bed. However, the 23B has a bigger bathroom and kitchen.
8: From what I was told, the RV converter is a single stage model, so a three stage converter upgrade is a must. With the limited battery capacity (~110 amp-hours, I'm guessing since there is just a single group 31 AGM battery), there isn't much point in anything but a 300 watt inverter for charging tablets, smartphones, cordless tools, and such. There isn't much outside storage, so I don't think there is much room for a secondary battery bank.
So, for boondocking, the solution is probably a solar array, coupled with having a small 1000 watt generator whose sole goal in life is to power the converter. The onboard genset can do this, but .1 gallon of gasoline used by a 1000 watt generator is definitely more thrifty than 0.2 gallon per hour of a 2800 watt genset. Plus, the 1000 watt generator can be moved a distance away for less vibration/noise.
Of course, I can tee off the propane line near the stove (adding a ball valve after the tee fitting for safety reasons), and plop a Buddy heater on the kitchen counter. This would definitely spare the battery and provide adequate heat, but I rather avoid that unless nothing else will do, especially if the coach is not completely winterized.
Another idea for long boondocking runs is an enclosed cargo trailer with a couple solar panels, a few batteries, and an inverter (so the Trend can be plugged into it for charging its relatively puny-tastic house battery. Expensive, but since I go to a festival and have the same campsite for months on end, having a trailer sitting there with full batteries ready to be plugged into is a better alternative to running a generator at night.
9: No solar, although I'm sure that can be retrofitted. I am not sure how much usable space exists on top, but I'm sure 200-300 watts of panels can be added on with a MPPT controller to keep the AGM house jar topped off.
10: It has heated tanks (electrical), and optional heated drains. Be aware that these eat battery life, as they are electric heating elements, so these are not that usable while boondocking.
Hate to be long-winded, but I like taking the time to doublecheck quirks about a rig before buying.