also, on the Honda vs Champion issue, both will parallel with one of the same brand. I have 1 Champion and follow a forum on them occasionally. It's not just about their wattage rating but also about what amp inrush they'll handle without tripping on overload. The Honda's are better. Depending on your AC brand/model rating, some can even get a single Honda 1600 to start and run their ac, (no other loads) whereas the Champion wont' start it on a sinlge unit, (but in that case would run it after the AC was up and running. Consensus was the Honda had superior inrush loading capability and overload tiem capability before shutting off, but it's almost double the cost per unit so.......
I don't run AC, so only have 1 Champion and it's been fine. The Honda is a little smaller (narrower) but similar weight.
Per above comments, pick a brand you can afford, buy one and trie the AC. if it won't start it, but the 2nd and a paralleling kit, then either brand should start the AC.
That way you can run only 1 unit when not running AC, etc
Calgary, AB Canada