Some time ago I posted an opinion about the Schubert C3Pro helmet and it's shortcomings. I've modified it several times to try to improve the ventilation (non-existent in my opinion) and the noise level. I wear trifocal lens glasses so I have never even tried the pin lock. I can't imagine adding another layer of glare and refraction. So I'm kinda fanatical about having my face shield perfectly clean, constantly taking it off the helmet at every other stop and cleaning it. So one day I take it off to clean again and think, "wait a minute, I have a windshield and glasses why do I need this stinkin face shield"?
The immediate surprise was how much quieter the helmet was! I thought I was imagining it so after about 10 miles I stopped and put the face shield back on, and again it was several decibels louder?
Needless to say, I don't use the face shield anymore and I finally like the C3Pro. I now have a quite ride with good ventilation and I still retain the ability to flip down the inner sun shade if I need it.
Just thought I'd mention it for what its worth, made a huge difference for me. You might give it a try with your particular setup and see?