I use a turkey fryer and the 7.5 gallon aluminum pot it came with. I have had 3 or 4 boil overs in my 15 batches, and it always happens when life is getting in the way. If I need more than 6.5 gallons pre-boil, I boil the overflow in a pot on my stove top, and add it back into the boiling wort somewhere near the end.