With my Nolan Flip Front I have used the Pinlock with varying degrees of success. My Arai solid has a small lever on the left side which when pushed slightly lifts the visor just enough to eliminate fogging. I would think Shoei would have something similar. I haven't had much problem with the Arai even in a downpour where fogging is usually present.
Those who don't wish to use pinlock can try a product called Cat Crap or Rain-X even spit works
Larry Ward
The Shoei RF models do have a similar lever that can be used to crack the shield. That is fine for helping to reduce fog in cool weather, but it isn't worth a darn in the rain, as when you crack the shield at the bottom, you also crack it at the top and that lets water run in on the back of the shield. I can keep the Pinlock shield completely closed in heavy rain and no water gets in and no fogging. Works for me. As I mentioned above the pins are eccentric, so they are made to rotate to get the proper fit so you have a proper seal, just like a storm window. If installed correctly, they work well. Just takes a little time the first time you fit an insert to the shield.
Was just going to say the same, all my RF models had it and I use them alot. Even in the rain and I don't notice that much rain coming in at the top and running down the shield.
I never used one of the discussed lense insert, but I did try some of those anti-fogging treatments (cream, liquid) that I got at the bike show once, think it was Zook, and it did nothing for me. Also if you wear glasses, the more layer of optic change you add the worse your vision is, at least for me. For example I usually wear regular distance glasses and a dark smoke shield. When its less sunny I use a clear shield, if I wore my regular glasses and add clip on type shades over them, there was a lot more distortion in the vision.
Ha-ha, see the Zooke product in the review Paco Bulto posted, D+ sounds about right.