I got the 2000 watt on mine. It comes down to whether you want to run the
microwave or not. The TV, stereo,
lighting,
furnace blower, water pump run natively on 12 volt. The king dome is 12v as well. You do not need an inverter for the
furnace. The air conditioner will not run off the inverter - you need shore power for that. The
refrigerator and the water heater run on gas, but need a wee bit of 12v as well. The 110v mode for the water heater will not run off the inverter either.
So what you need an inverter for is the
microwave and any 110v appliances you are going to carry - like a hair dryer, a crockpot, coffee pot, toaster or satellite receiver.
Anything with a heating element will draw down your batteries quickly. A satellite reciever is probably only 50-60 watts, so that is not anything to worry about. You can probably run a
microwave (1000 watts)for 15-20 minutes without worry. A coffee pot (1500 watts) may be good to brew and then shut off - you don't want it to keep heating beyond 15 minutes. There are tables online that give you sample appliances and their expected draw over time.
The power to run the inverter is around 20% of the wattage it's generating. So if you are generating a low amount - like 60 watts for a satellite reciever - it's going to use 12 watts for the inverter. The good news is that they only provide what you are currently needing.
I figured that my loads would be
light most of the time, but with the bigger unit, I could run the microwave on occasion. Otherwise, besides the price, there is no downside to your batteries to select the bigger unit for
light loads.
Make sense?
One last thing - if you get the bigger inverter, they will wire up the trailer so that every outlet will get inverter power. If you go with the small one, they wire in a couple inverter only outlets - one in the video cabinet so you can hook up a satellite decoder.