We have an Ultrex deep fryer (discontinued line previously sold on HSN) which still works great. The reasons we selected our model would still apply if we were shopping for one today:
Capacity - ideally 3 or 4 quart will allow for a good quantity of food to be cooked at one time, while not being so large that you have to store tons of cooking oil
Heating element - now they are all pretty much the same, the submerged heating element. Look for one that has 2 "thingamagoobies" on the element to register the temperature, and is raised above the bottom of the container so it doesn't burn whatever drops
Digital/Manual controls - I prefer manual as the oil splatter makes the digital difficult to read
Magnetic power cord - kids or not, this is a great feature
Basket options - narrow and deep is better than wide and shallow
Pitmaster - Green Card Q
UDS, SJS/Tamale Pot Smoker, Alton Brown Flower Pot Smoker, Blue Ember Gasser, Weber Performer
Newly elected into the Hall of Zero's (Noobians v. Veterans Throwdown)
I'm a lumberjack, and I'm okay. I sleep all night and I work all day.
I cut down trees. I eat my lunch. I go to the lavatory.
On Wednesdays I go shoppin' and have buttered scones for tea.