i have a coleman ac with heat strip on my sleeper. works good, will freeze me in no time and managed to keep things defrosted if not toasty at 20 below. the heat strip is only 1200watts.
that makes it a little anemic when things get below zero.
i went with a gas rv generator. mine puts out 3600 watts. more than enough to run ac, tv, ref, and microwave at same time. gen is very quiet which i like. yes i have to stop at a gas pump every couple days, but for me I find its not a great inconvience. the gen runs about 4 hours on a gallon of gas. price of gen about 1500.00, price of ac about 600.00 gas tank, side box, misc fuel line, electric connections, mounting bracket for gen less than 500.00.
installed everything myself, with a little help from my neighbor to get the ac on the roof.
note: the ac broke during the first year. the compressor came loose from its mount breaking the lines. coleman replaced the unit under warrenty. had the new unit modified. the compressor is held on the mount by a couple butterfly push tabs. these had vibrated off allowing the compressor to bounce off the mounting pins. a couple of small holes drilled in the mounting pins and two cotter keys keep the butterflys from popping off.
based on current fuel prices i figure unit has paid for itself already. its been on the truck for two years this month.