Chance, I have converted to a foot switch after 5 years and can't beleive I didn't do it sooner!! I would recommend useing the off and on eather the one you keep your foot on to saw and lift your foot to stop, or the one you press down to start,take your foot off and the saw continues to run,than to stop the saw you tap the pedal and it stops. Eather one would be the best to use instead of a varable pedal. Thats works great for a sewing a machine but not for cutting wood!! You run the danger of snapping a blade in a turn on thicker wood and as stated in the reply above ruining a fragile fretwork.
One other thing, if you have been scrolling for a few years prepare to break the habit of turning off the saw with the switch thats on the saw!! I am still doing that but it will come around! I also have an old electric clock(the one with a cord attached to plug into an outlet) that I have connected to the pedal to keep track of the time it takes to cut a project.
Ervin