My Spirit has the stock drag bars which appear to be different from yours. I picked up a used National Cycle Deflector just to see if I'd like it in the winter. By conventional wisdom it is too small for the purpose. In practical use it does exactly what I want...keeps the worst of the wind off my chest. I planned on using it only in cold weather, but it never came off the bike.
Whatever you get, give it a fair trial. It took a few weeks of playing with the angles and placement before I found the sweet spot with no buffeting or bizarre wind noise. (My bike developed a bad exhaust popping for two weeks until I adjusted the height of the screen down about 1/2 inch. Low and behold the popping ceased...it was wind hitting my helmet just wrong that made the sound.
After a year with one, I can say I would have a bike without for running around town, but for getting out there I will always have one, and I never thought I'd like it.