My oldest ones are four years old and I've only damaged one of them by leaving it too long (at least several months) in a device in a discharged state. It's damaged as I've been unable to charge it in the typical AA / AAA type chargers.

I first found these in Circuit City and Best Buy but I couldn't find them anymore two years ago until I came across them at Costco sold in a blue case for $25 (the best price I've seen for this bundle).

The bundle contains: 4x AAA, 8x AA, the open face charger version*, and C and D shells. The shells allow you to use the AAAs (never tried it myself) in devices requiring C or D cells.

*The open face charger version is not as nice as the version that includes a sliding cover. The open face version requires two or four cells to be charged at a time where the covered version can charge the cells individually as well as any combination. There were some bundles sold with the covered version but I got my covered versions back when I would purchase these in a blister pack 4 cells plus the charger.

I typically use these in my media remotes and wireless console controllers (Wii) but last night I put them in my kids Slash transmitters.