Need advise on which turkey fryer / steamer to buy

I agree with the aluminum, it transfers heat better and it doesn't sound you'll be using it for anything that requires SS.
I don't know about the frying part for turkey. I did a few, but the Big Easy turns out about the same product without all the mess and hassle. They do make great fish or fryers for fried chicken though. Plenty of BTU's to maintain a good temperature.