I have a Spy Capsule Keychain Lighter from EDC depot that I filled with fuel 10 months ago. I don’t use it, don’t smoke, I just wanted to see how long the fuel would last. I lit it once a day for a while then went to once a week. Now I only light it about once a month and guess what? It has lit every time so far. I guess the O-ring keeps the fuel from evaporating as well as keeping the water out. Compared to a Bick, of which I have many, you can light the peanut and set it down. For what its worth.

http://edcdepot.com/spycapsulekeychainlighter.aspx