I remember when the G7th capo first found its way to our shores from the UK. As I do with most gear fads, I withheld judgement until I had a chance to use it onstage. Nowadays, the G7th is the only capo I'll take onstage with me anymore. It really is that good. I find that on a Crowdster, the Shubb S-1 is a better fit, but for all other guitars, including my workhorse Renaissance RS6, the G7th rules.
The G7th capo is the only one I've ever used that offers true one-hand operation, in both the tension adjustment and application/removal. To attach it to the fretboard, you just squeeze until the tension is appropriate, and let go. To remove it, you just pop the little switch on the bottom, and it's off (and the newer geometry of this capo means it can go on your headstock, unlike the original G7th). Yes, it's a bit on the expensive side, but once you master its usage, you'll never go back.