I have the Brinkmann from Home Depot. The pot is just big enough for 5 gallon batches. I start with about 6.5 gallons for a 60 minute boil. You have to be very careful at the start of the boil so it does not go over the edge of the pot.
I have since gotten 10 gallon stainless steel pots and a Bayou Classic SP10 propane burner. It is much faster to heat the wort. I now use the turkey fryer to heat my water in the HLT.
I also do not worry about aluminum. If you boil water in it to create an oxidation layer you should have no problems. I still use my aluminum pot occasionally and can tell no difference from brews in the steel pot.
On the Brinkmann there is a heat sensor switch. Disconnect the wires from the switch and connect the ends together and the flame will not cut off.
I don't know anything about the other one.