Thanks Scott - that's the thing I was looking for, and the use I had in mind.
I don't like leaving a propane burner unattended while it's heating up the strike water, but this should fit the bill quite nicely, even with 13-14 gallons of water (and save propane for when I want to have a nice, rolling boil)
Yes! Not only would they need to be on dedicated circuits but the circuits would need to be rated at 20 Amps (or more). The 2000W heating elements will draw about 17 Amps each (Amps = Watts / Volts) and would trip a 15 Amp breaker. The 1000W bucket heater that I use draws about 8 or 9 Amps (of course, it takes longer to heat the water).