I agree with Mac - set it and forget it. I have a Jet and asked the same questions before making the purchase. I went with the non - variable and have never reset the belts turning plugs. If you are going to do bowls and an assortment of stuff, the variable might be nice. If you are turning plugs, save the dough and buy a quality chisel.
I drill and do all the things you are doing and have not had to change speeds.
Just my opinion.
