Thanks for all the feedback. I think I am going to go with the un-switched source. I've had the GPS for two weeks now and just got to open the box this morning. So I look at the wiring harness and see there is about three feet of cable before it splits into the various outputs (power connection, headphone jack, microphone jack, mini-usb).
So am I correct in assuming that most people would route this section of cable back under the gas tank into the seat area so these other connections are available in the seated area? (as opposed to keeping this section somewhere up front around the handlebar area?) Can you do this without removing tupperware and/or the gas tank?