Well I've been using these in Smoke alarms and Window alarms and they've done an excellent job so far.
With normal Ni-Mh batteries, these alarms would function fine for about 9 months, before that infamous smoke alarm beep to tell you the battery is low, or the window alarms not sounding when you bash 'em.
I first purchased 3 of these batteries in February 2008 and are still going strong to date. I've never actually charged them -- they come charged and stay charged!