Information on 14250 battery

As it says, I would like to know if anyone has experience with 1/2AA (14250) batteries. Just bought a DQG SLIM AA which take both sizes with proper tube. Sent George an email but nothing back yet. The most common types appear to be Saft and Xeno but just in availability.
Thanks.

Following. I was just looking up the same thing, except mine is for temp logging equipment. I was wondering what the best (if any) rechargeable button tops there are.