Replacing Air Conditioner - which one?

I've got a Dometic Brisk Air II in my current Freedom Express and having previously owned Carrier AirV, Coleman Mach III Plus, and the original Dometic Brisk Air in various trailers we've owned in the past I can't say the Brisk II is any quieter or more efficient ... maybe in lab tests but out in the real world that's not been the case for us, it's still noisy as heck and we only run it when absolutely necessary. Aside from the aforementioned, a relatively new entry to the market is an Australian product now being marketed in the US by Atwood, the Air Command series, which claims to be truly more efficient, with their 16,000 BTU "equivalent" model capable of running on a 2000 watt genset such as a Honda EU2000i. Would interest me if true.