I have the same Slipstreamer as Phil. It's certainly a quick on/off, just a few minutes even if you put on/remove the clamps on the handlebars. Recently I did have to change out the wingnut-like bolts that hold on the windshield bars to the handlebar clamps. These weren't all that secure to begin with as they seem to always work loose at least once a day on a trip, and I'd have to use a pair of pliers to get them really tight. So I just went down to the local hardware store and picked up some allen head screws to replace them. Since they are the same size head as the handlebar clamp screws, I don't have to carry another tool to tighten everything up, and the allen heads with a wrench is much easier to adjust then the stock wingnut-like screws with a pair of pliers routine.
I'm not a big windshield fan, so I only use one on long trips, or when it's heavy bug season. The Slipstreamer Viper S-10 suits my needs just fine for the $70 it cost....even with the hardware issues.
