Picked up a set of these just for fun. They seem to be a good quality battery, haven’t noticed them going down any faster than a standard store bought 9 volt. They look very cool, everyone who sees them laying around has to ask about them. If nothing else, try these out because they are the same price or cheaper than regular 9 volts and they look a lot better.

I love these batteries. I only use them in my effects. This may sound weird, but different batteries have different sounds. These batteries give you a really vintage vibe.

Plus, they last for EVER. I still have the one I put in my Wah Wah last year, and it shows no signs of powering down.