I use a 2000 w element in my boil kettle, no insulation, it takes some time to get a boil but a 20amp gfci is far cheaper and well I already have them installed. My setup has no control panned (yet) although I do have a switch mounted on the kettle. I boil so I have 5.5 gal in the fermenter, and that is volume above the ball valve ( I don't use a diptube)....so 2000w 110v IS enough for a full boil.
Don't take any more faith in anything I say than you would anyone else on the internet. If you listen to what I say, then hurt your self or break something it is your own fault, I am just expressing my opinion or experience.
THINK for your self!!