My personal choice when it comes to cooling the RV is to keep it as warm as I can to be comfortable inside. My reason for that is so when I go outside the heat isn't such a shock. Same goes for coming inside to the cold when its hot outdoors. I set the thermostats on 79 during the day and about 73 at bed time. Running them on auto compared to constant on will help keep the humidity down, too. Also, I only run the a/c units on low fan as they will remove more humidity that way compared to being on high. It is the high humidity that makes me uncomfortable. If the humidity is lower, the temperature can be higher.
We have a friend who keeps their rig so cold inside and the fans running constantly that it feels cold but damp. I have tried to explain to her the logic but she doesn't get it. Yet when she comes into our rig she always says its so comfortable. LOL
I have camped in 100 degree heat at the beaches and never had an issue. Phillip