Not sure if Rheems gas vs electric water heaters make much difference but when I was working apartment maintenance a couple of years ago we had alot of Rheem failures within the warranty period. I'd also look at the conditions for the "lifetime warranty" to see if it makes sense.I am in the process of replacing a 40 gallon electric water heater. Looking at a Rheem. They offer a 6 year ($409), 9 year ($549), 12 year ($739) and a variant called a lifetime water heater ($1100) that is lined with some type of plastic that prevents tank corrosion. I am trying to understand is this lifetime unit worth the extra cost. Any opinions on this? Would I still have anodes to replace in this plastic lined variant?