[SirDrake]

I upgrade our A/C with the Atwood Air Command 15k unit this summer.
It was fairly easy to install (with some help swapping units on/off the roof).

It is quiet, cools extremely well, and the heat pump works nicely to take the chill out of the air (we used it in auto mode one weekend and it works great!).
The remote works great too, can operate the unit from bed.

The only issue I ran into was that I had to grind a little off the edges of the 14x14 opening to get the new bracket to fit (my opening was a little rough, took the dremel to it and opened it up a bit).

Then I had an issue with the trim ring that covers the opening, it would not fit back over the opening correctly with the new A/C plenum in place.
I spun it 180 degrees, placed it where it fit best and drilled new mounting holes.

I think I paid about $675 for the unit and the ceiling kit as a package deal on eBay. Shipping was included and it was delivered by a trucking company, it came bundled on a palate.

So far we love it. Hope this helps your decision.