A few things about the C3 (not the Pro) based on my particular purchase...
The flip front never seems to close properly--it feels like it latches on one side only. Couldn't tell if that was the actually the case, but it made me apprehensive.
The ventilation is so-so in comparison to my RF1100. Noise is pretty well controlled due to the thick padding and the chin curtain. You will still need earplugs though.
The chin strap is a ratcheting type, which isn't as comfortable as a double D-ring, at least for me. It's further back too, so it digs in a bit. There's no easy way to use an underseat helmet hook. I think Schuberth offers a locking accessory link to address the matter.
The outer visor is okay, no strong detents like on the RF1100, so the wind will push it closed at fairly low speeds. It's an odd shape towards the bottom. The inner drop-down sun visor mechanism is easy enough to use, but the visor itself has some sort of ant-fog coating that itself fogs up. The visor bracket is a VERY finicky design, so taking it out to clean is no simple task. It didn't break on me, but I can't see it holding up over time.
Last but not least, beware the "Mark Of Schuberth". The interior radius of the shell tightens around the forehead area, but it's not immediately obvious. This is bad news if you have an oval or egg-shaped head (from the top--take a photo and you'll see). It takes about 20 minutes for the hotspot to show up, but when it does it's pretty hard to ignore. Leave it long enough and you'll end up with a mark on your forehead (nothing serious, it goes away). My helmet was sized properly but it didn't work out. The retailer had ZERO interest in helping after money changed hands, so be totally sure.
Conclusion: Good quality German product with some quirky design features that may not fit properly. Mine is sitting boxed up on a shelf, a hi-viz warning about the perils of helmet shopping. The Pro is supposed to be a different beast and I have no experience with it.
