The 3000 is a nice unit, but it's fairly large and on startup, of the A/C compressor, I am not sure, depending on the A/C units size that you'd be able to run the A/C, TV and microwave at the same time (again, mostly depending on if you have the 11k unit or the 13.5k A/C unit).
A number of folks have gone with 2 2000 units and hooked them together and I think that could cut it with running all 3 at the same time. Honda makes some great units. Yamaha does too. You can get a kit for the Hondas to run on different fuels, namely propane, here is a link to the Yamahas, where a company does all the grunt work of carb conversion for you:
It isn't cheap by any reach. I have been looking at the issue for a bit over a year and came to the conclusion that I got 2 fantastic vents in the Safari and that if I boondock and need cooling, the cost of 2 gens to run my 15k BTU unit would be cost prohibitive in my case (at least today). So right now, I personally am leaning toward the Yamaha ef2400is. Has the meat to keep the batteries charged, both fans on high, microwave, lights and TV and later if I really want the A/C unit to run, I can get a second unit and connect them. Plus, since it runs on propane, there is no gasoline odors, etc while in transit. I could in fact place this unit in the back of the Suburban in a rubbermaid or in the trailer and not get high on gas fumes.
That's my take, eveyone has a different need though.