I bought them 6 months of so ago----SilverWing specific.
Tried-----nothing special, took off. Installed again and in conjunction with new Givi Adj shield they work in keeping "dirty air" in check----I keep them out, blocking air from knees/upper legs. Should work well in cold/rain.
Warning: the suggested and bolts furnished method of mounting is at best Mickey Mouse. Little diddle time----6mm bolts with fender washers from inside, pal nut and flat washer against plastic on outside, install wing, another nut and final acorn nut---gee you think I had a GoldWing.....with chrome acorn nuts. Be careful with drill depth.
I see these are good addition to Silverwing.
Also I somehow found lower windguards made for Reflex------Flat plastic is about 4 inches wide----I installed with tiny sheet metal screws under floor mat----just makes front of bike a little wider----actually keeps air from going up nose and feet drier in rain. Any 4" or so wide flat, flexible plastic should work.
Neither of these seem to have any effect on gas mileage------I get 50-60 MPG US. mostly in the high mid 50's and even once 61. Funny trying to save gas techniques usually yield same as just riding