You will love your Berkshire!
We had a gasser and the diesel really isn't that much more expensive to own. We would get 8-9 mpg in the gas coach and we get 10-11 in the diesel coach. No more screaming over the engine and no more being blown all over the road every time an 18 wheeler passes. The Berkshire handles great on the road. Going up a hill or mountain in a gasser is just plain SCARY compared to a diesel. If the screaming, sounding like it is going to blow up sound of the engine isn't enough to give you heart failure, the fact that the gas coach slows down to a VERY slow speed as it "tries" to get over that hill or mountain will!!
As far as the water heater. Once you get used to it you will love it. To me, it is just like the one in our house: turn water on, get to right temp, shower, let water flow, rinse, done.
I think once you test drive your new coach, you will see what we are all talking about. Then you only question will be "why didn't we do this sooner"???
Good Luck, and keep us posted!
Rick and Karen
2016 Berkshire 38A
2011 Honda CR-V toad FB