I have a national fly screen, a little better than going w/o but way better in the summer than a full screen.  w/o I get to 50 before the blast slows me down.  w/flyscreen I'm good to 70.

I've got the clear SpitFire on mine and love it.

Here is a past post with other members comments.
http://suzukisavage.com/cgi-bin/YaBB.pl?num=1231020427

WebsterMark wrote on 01/31/09 at 09:01:53:

I have both a National Cycle Flyscreen:

Useful for carrying flowers behind; and the National Cycle Street Shield:

Taken last year while on tour.

Summertime I usually run naked.  If I'll be making a freeway trip I'll slip on the Flyscreen.  It takes the wind pressure off the body and allows sustained 70+ without fatique.  Goggles required.

Winter riding, and on tour, I mount the Street Shield.  This big boy (17") keeps the cold winter wind from running it's icy fingers down around my neck.  On tour, wind is deflected off the face, allowing riding with mere sunglasses in lieu of windproof goggles.  Mine adjusts to have the wind hitting just above the browline -- wind in the hair, not in the face.