Kites and wings....have used my fair share of valves and the variations over the years. My current setup on my Neil Pryde would have to be hands down the best I've used so far. This is the valve type that you see being used on other inflatable craft like SUP's. It has the centre push/twist valve in the middle. Simple to use and and reliable.
My previous PPC was fine, but a PITA as you had to screw in two parts to use, and when cold it was hard to release after a session with numb fingers.
Kites....Core, having to use that little release plastic bit. I don't know...but if flaps about if you forget to stow it and is fiddly to use.
Duotone...****. The release part (if you don't use the valve down near the wing tip) is sharp, and if not careful will (has damaged every kite I've owned), so you need to carefully replace the cap when storing your kite. They even reinforce that section where the valve touches given that issue.
Would be great to have an industry standard out there.
Other variations that are good?
