The problem we have had in the pass with non commercial fryers is production. We ran a couple of concession stands a few years back and tried everything from turkey fryers to large FRY Daddies. None of them can keep up with production. In one of our stands we installed a small commercial table top fryer. It ran circles around the other fryers. Ours was a 220v but you can purchased a propane / natural gas model. The down size is cost. You are probably looking $400+ for one.
There is nothing more frustrating then a customer waiting for fries.