They're not cheap, it's definitely a coolness, gadget factor to it. But, the RFID shielding is legit. I remember about 5 years or so ago I tried to go cashless and only carry my cards in a money clip, but they didn't have these so it didn't work out. I gave up on my cash-only experiment so this might be the route
These aren't cheap before the "why would you pay X for a wallet?" comments start up
Saw an ad yesterday I've been looking at them all day:
RIdge: Way too minimalist and expensive with no features. Plus, their website says the elastic wears out after a few years?
But these are popular
Another one, that I started looking at was the Fantom:
One I'm thinking about is the Dango:
Looks like the industry is starting to take off and a lot of new models and vendors are showing up.