In the for what it's worth department I'll toss this out. For 20+ years I worked professionally on RVs. On service calls to small dealers lots, I carried a Yamaha 2400 in my truck to save the aggravation of pulling extension cords on units located a good ways away from the garage. What I learned with AC units is whether my genny would start them was a **** shoot. Most often it would, but other times it would stall out. There never seemed to be any pattern as to which makes or models would run, although more often than not they did run.
It was the same thing on service work. Up on the roof with a clamp meter on the compressor there was considerable variation in amp draw making it hard to offer a simple rule as to what will work with what. I know what the service manual says, but there are a lot of variables that still come into play. I think that leads to a good deal of variation in self-reports. I also have a Yamaha 2,000 and it is the same story with that one.