My Stihl helmet has a knob -- as I recall they had two price levels of helmets when I bought 4-5 years ago.
I do think Labonville makes the best chaps. I own a pair of the full wraps and have been pleased with them -- very tough. After time they become very comfortable, and give some extra warmth in cold weather.
Really, the only difference between regular and full wrap is in the ankle area, where full wraps go around back for extra protection.
I have looked into dedicated chainsaw boots, and they all seem heavy and uncomfortable. So far my aluminum-toe Irish Setters have been a good boot, though they won't stop a saw other than the toe box (and even that won't last for long).
You will find that chaps aren't necessarily manageable in real hot weather, so start to think about what's more dangerous -- chainsaw or dehydration. I can pretty much tell where the tipping point is. In real warm weather, I will wear chaps over shorts only as long as needed for cutting, then take them off for other work.