Hi Paul,
I'm new to looping, but I do not see why you would want a second loop to be of a different length than your first "drum"loop. (The whole idea of looping is to have them in sync...)
Whatever you decide to go with, the Auxiliary switch will greatly help out your live performance. I purposefully choose the RC-1 to minimize all the extra stuff I didn't want to use, and it works out really well.
You can make your own double switch if you're handy. Mine uses two normally closed heavy duty momentary switches attached to a short section of stereo 1/4" patch cord and I love what it does for the looper. The double-tap thing is just aggravation. I knew that before purchasing a looper, so I had the switch built before I got the looper.
