I'm thinking of getting one for when I take trips up to my parents house (couple hours). Not sure if it will work with a drag bar though. Kerry, any thoughts?
I don't know much about drag bars. Do they have a lower profile than the stock handlebars on either side of the handlebar clamps?
Take a close look at the photos on my Plexistar II page (http://www.bbburma.net/Plexistar2.htm). There's one labeled "What the rider sees". It will give you some idea of how much adjustablity is left in the handlebar clamp area. (When the metal rod is bottomed out inside the plastic holder, I think there is still an inch or so protruding - before the bend.)
Now look at one of the side shots. This will give you a feeling for whether you could put up with more or less of an angle on the windshield (which translates directly into how much of the afore-mentioned rod is inserted into the plastic holder).
Next, look at one of the head-on shots. See the amount of space between the bottom of the screen and the headlight? It looks like you could drop the shield another inch or more ...
... but the shot labeled "How the bottom mounts attach to the fork" indicates otherwise. There's only about 1/2" to 3/4" to be squeezed out down there.
I don't know - did this help at all?
EDIT: Changed link from sisna.com to bbburma.net
Well, looks like I'm going to have to try it and find out. Thanks Kerry.