I won't buy a camper or a toy hauler without a built in genny.
Just been too nice to have too many times to not have it.
When dry camping I run it for making coffee in the morning without needed to pull out the Honda 2000.
When traveling when HOT, we stop anywhere and can run the A/C while eating lunch. This summer we did a 24 day trip, I think it was over 95 degrees over half the time.
When traveling when HOT, we can also stop, run the genny and leave the dog in the A/C.
Our 2011 camper only has about 50 hours on the genny was we try to use it very little, but its been really handy. And we do have a Honda 2000 we use in the evenings when needed/wanted.