The three position switch works great for touch and goes. Just click them up and pour on the coal and your off. The knob takes a second longer to get the flaps back up.
My newer radios don't have 3 position switches, so I am forced to use the knob. It is nice when you are lowering the flaps, you can roll them in gently. My T28 walks in at a ridiculously slow speed, but it is rock solid stable. Its like watching a movie.
I wish I could use a knob to lower them, and then hit a switch to retract them.