I have the batwing with 9" shield (NOT the new "spoiler" shield), and the accessory wind deflectors, on my 900c. The wind protection for me (5'8", and looking a couple inches above the shield, due to my Mustang seat) is great up to ~60 mph, but after that the buffeting gets pretty bad. I'd been thinking about either lowers, the new spoiler shield, or the Laminar Lip to help with the buffeting.
I'll be interested in hearing how you like the 9" spoiler shield, as my previous experience with a GIVI spoiler-shaped shield on a sport-bike I used to own was that it didn't make too much of a difference with smoothness of the airflow.
Otherwise, I love the look on my Custom! :-)
'04 DL650 V-Strom
Gone but not forgotten...
'08 VN 900 Custom in Kawasaki racing green
'95 Kawasaki EX500 Ninja
'88 Kawasaki EX500 Ninja (track bike)
'85 Yamaha FJ1100
'83 Honda CX650 Custom
'87 Yamaha YZ125
'84 Honda XR80