Originally Posted by Blackhat6mike
If you plan on running anything else while running just one AC, like coffee pot, microwave, water heater, curling iron then a 50amp circuit is a must, not to mention running both AC at once. If you spend time in the south, you WILL run both ACs. Go for the 50 amp.
I always see people writing this but we have never tripped a breaker in our RV. It's 30 amps and I use the AC (all day) and the microwave at the same time. As we "speak" I am running the ac and a convection oven to bake cookies. We are also able to run two space heaters at the same time without tripping a breaker.
That said, I'd get the 50amp option. You don't have to use the 2nd ac (or additional electrical power) but it's nice to have the option and at resell, it might be worth (a little) more money.