I hate the idea of the start/stop function and it should be mandatory that there is a shutoff button. Last thing I need is to be out in the middle of nowhere and have the engine shut off and then won't restart because of a starter failure. I ran into this situation on a trip in Death Valley, with my first Cherokee. Starter was intermittently working (starting to fail) so to prevent a total failure, anywhere we stopped I just left it running. Waited until we got to camp to shut it off. This minimized how many times I needed to start it and allowed me to continue on the trip (this was day one of 4). Got home and replaced the starter and all was well.
Put this start/stop crap on street driven only cars, where a tow truck can come pick it up but leave it off anything designed to go offroad (i.e. all 4WD vehicles).