I recommend listening to this podcast on the Energy Show if you are looking into switching out your gas water heater for a heat pump water heater.
What You Need to Know About Heat Pump Water Heaters
I couldn't agree more. We had a new heat pump installed without a surge protector and now it has taken over a month for the replacement parts to be available after the heater stopped working likely due to a power surge.
They are inexpensive and easy to install! We have an Intermatic AG3000 surge protector installed at the 220V disconnect now and it took less than an hour to install.