I was told by an independent plumber to stay away from heat pump water heaters. He said that he had a few customers with them and they are always breaking down. So, I don't know.
I have well water and a water softener. Because of that, the anode rod causes the water to smell like sulfur. I have 2 options, buy one without the rod, or buy one with and then remove the rod. If I remove the rod, it will void the warranty of the heater, so I'd rather buy one without.