I don't use it, mainly because I have a few months left before I can upgrade my iPhone. I don't think we're quite there yet with this kind of tech being the norm. It's not a wallet replacement.
I'm actually leaning toward using one of the so-called bridging products, like Plastc. A credit card with an e-Ink screen (like a Kindle) and you can load all of your cards onto that. Then you only have to carry one card. I think it's a pretty cool product.
I've slimmed my wallet, made by Dash, down to my Amex, Mastercard (if a place won't take Amex), debit card, driver's license, and health insurance card. Everything else I load into an app -- I'm using Stocard. It's gone so well that I'm not sure if I'll do Plastc or not.