If you need to eliminate head buffeting with the windshield, lowers will definitely do the trick.
I used Memphis Shades lower fork brackets, and made up some lowers from some 3/16" Lexan.
The brackets are for a VN900 but they also fit the Speedmaster/America lower shrouds.
Here's the setup on my wife's '07 with a Clearview Summer shield
Here's a different style with a Cleaview Roadster shield
HTH,
H.