I started out with the Blichmann Boilermaker 15 gallon kettle for 5 and 10 gallon batches and got great use out of it. You just have to be very careful during the hot break. I now use that as my HLT after upgrading my system to a 3 tier brewstand. My new boil kettle is a 20 Gallon Blichmann Boilermaker, and all I can say is...IT IS GREAT! No chance of a boilover! So I don't have to be so careful with turning down the flame during the hot break. Plus, it's only a few dollars more than the 15 gallon kettle. Blichmann is a bit pricey, but the way I look at it is: I'm going to be doing this for a very long time so I want something that lasts, it has every feature needed like a brewmometer, dip tube, sanitary ball valve, sight glass, lid easily hangs from the handles, can add a false bottom if later in life you want to have a larger heated mash tun, it's made of a great quality stainless steel, PLUS it looks bad-ass in my brewery.