I can't comment in the C, but we use one at home. They're pretty big, so you'd need to make sure you have a good space for it, and it needs to be open a bit on the front and back for air intake. And then you'll need to figure out a way to rig the hot air exhaust out the window. The little shield thing is made for double hung windows, but I'm sure something could be figured out to go out a sliding RV window.
But I think your biggest concern is going to be the noise. You're right, they're loud. Loud. Everything is there in the room with you, and in an RV it would even be a smaller space than at home. Not something for light sleepers, but if you like a "white noise" that will drown out anything it might not be too bad, or if you're turning it on during the day or to chill it down for the evening but not sleeping with it, that would work.
I've never looked at the draw on ours so I can't comment on the genny, but I would think it wouldn't have a problem with it.
