re: Oil for fry daddy?

For small vessels like a Fry Daddy, I'd just use whatever REFINED oil is the cheapest that puts out a product that tastes good. These are going to be all of the oils that you're used to seeing in the vegetable oil aisle. They're all going to be similar in performance and flavor profile, though some people can taste the differences. Start with the cheapest one and if you don't care for the end product, move up to the next most expensive one. Stop when you find one you like. For a Fry Daddy, it doesn't hold that much oil to begin with, so replacing cheaper oil more often isn't a big deal. You're also not likely to ever fry anything long enough to need one of the ultra clean oils that has a smoke point that will allow it to endure hours long frying sessions. Sure for long cooks like turkey fries that take a huge amount of oil that you'd like to be able to use more than once, the high end expensive oils would be where I'd tend to look. For every day frying of fish, seafood, potatoes, frozen stuff out of the freezer, chicken (unless I'm pan frying, then LARD, GLORIOUS LARD), etc. in a Fry Daddy where tossing out the oil means losing a quart or two, I'm going cheap.

Under no conditions would I deep fat fry with any vegetable oil other than a refined oil (e.g.: olive or other pressed oils), as their smoke points and flavor profiles are not a good match for deep frying.

Lard and tallow are good (some would argue superior and they'd have a case) for deep frying as well, but I assumed you were strictly asking about vegetable oils.