Worth spending the money
$52 seems like a lot for an inflator head, which is what you're really after when you buy this, but I've been through a few, and it's worth the money. Why? The ability to screw the head onto the valve to lock it on, prevents any CO2 seepage and you get a 'clean' tyre inflation. I also used it once to top up a slow leak to get home, then I could still use the same cartridge (that I had kept closed) a few weeks later when I had another flat. So that wasn't a wasted CO2 cartridge.