I made a hard bimini top. Works great. I've had it over 120 mph and if anythign, It braces the windscreen. I only use it on weekend rallies for the to and from ride so I'll have it when rain hits. It keeps all but the left arm hanging out on the door dry at freeway speeds.
Here's a link to some pics and the construction.
Lonestar Classics Forums • View topic - Bimini top
Oh, and it's off and on in 15 minutes. Mounts to the slot on the windscreen with 4 1/4" carriage bolts ground down to fit the slot, and 4 hose clamps to the roll bar.