Using the HLT and MLT from my Propane setup, I have found the electric turkey fryer to be a viable way of brewing, but they need a little help if you are going AG. With the pot reasonably full, I have a problem getting it to maintain a boil. I got around this by insulating the cavity between the tub and the outer housing with Fiberglass insulation, then wrapped the outside with a metallized foam insulation. I also use hot water from the faucet, which comes out at about 135 degrees.
I will heat my Sparge water first usually up to about 195-200 degrees and pump it into insulated cooler #1, my HLT. I will then heat the Strike water (again preheated to 135 degrees) and it will get to Strike temp in about a half hour. I then mash as usual in cooler #2. Biggest pain is getting the wort to boil, you have to keep the lid closed, but it will boil over at hot break, so I keep a close eye on the thermometer as hot break approaches. The foam that forms from 195 to boiling helps insulate the wort as it heats, but keep an eye on it. Once the initial foam dissipates, you will have to find a way of keeping the lid open a crack to keep enough heat in to keep it at a rolling boil.