Location of Heating Element in Keg/thermostat

[Regs]

My buddy and I had a difference of opinion as to the ideal location for the heating element we're going to install in our keg/boiler. I want to put it in the side, horizontally, he wants to put it in the bottom, vertically. Any pros or cons to either? Also, will a 240V baseboard heater thermostat work for us to control the temperature and current to the element? It seems like if it would, I'd have seen something on here about that. Any thoughts?