Went down south in a pup without AC and brought one of those portable ( not really portable because they're big, but has wheels on the bottom) AC units. Stored it on its back during travel, then put it up on a counter by the door and vented it out the window. Just zipped up all the windows and zipped around the hose. Worked great! No problems with electrical, but we did only book 30 amp sites. This was the only trip that we needed AC for, as just unzipping all your windows usually works pretty well if you are under 90* degrees.
Our new htt has AC included on roof mount, and I do like that. Given the choice between buying a unit with AC versus not having it I do recommend it. Lugging around a portable AC unit eats up a lot of space.