I can help you with one issue: fog and rain.
Normally your windshield is just below your eye level, you should be looking over it, not through it.
The shield helps more with the air blast hitting your body, and to some extend the air is channeled up over your head, if your head is in just the right place.
Having said all that: put RainX on your windshield and the shield on your full face helmet. If you have somehow never used RainX, you are in for a delightful surprise. And put it on your truck windshield too.
For all my cars I buy the washer fluid with RainX in it (the orange stuff), so I dont have to bother applying it to the windshields anymore.
If the shield on your helmet is fogging up you need to crack it open just a bit, and sometimes all the way when you stop for a red light.
HJC makes helmets with a pinlock insert that is a double layer of plastic with an anti fog material on the inner side. I have used them when its very cold up here in NYS, but the problem I have is my glasses fog up anyway, so I have to crack the shield open a bit anyway to keep my glasses from fogging, so I dont need the insert. But if you dont wear glasses they are worth the cost in the rain.
Last edited by KCW; 04-29-2017 at 08:58 PM.