Much better than presta. Do you really need this? Probably not. But I'm sure most cyclists buy less important things for far more money. So why not? It works. It's convenient. It's easy. There's no reason to not use this, unless you can't afford it.
I just changed all 9 of my bike over to this. It's great not having to screw, unscrew and rescrew the presta valves every time I need to fill my tires. They seem to fill much quicker. We'll see how they deal with sealant, but so far so good'
