Re: surefire rechargeable 123 batterys
i asked the same question a few months ago & got no responses. I went ahead and ordered the charger/battery combo from surefire. I am very pleased. They take a while to charge the first time but after that they charge within a couple hours. The output is the same and runtime as far as i can tell is the same. Surefire reports runtime is possibly cut in half, but I have used them hard multiple times and they held up the same as disposable batteries in my opinion (not very scientific i know). i've used them in a streamlight tlr-1s, surefire lx2, and everything else i have that runs a 123 without any issues.
edit to add: the charger and batteries are protected. they won't blow up your light/device, and auto shutoff on the charger when full. charger works in the car too. Should mention, some single cr123a lights absolutely won't accept rechargables because these batteries have a much higher output than disposables. That's why many lights, such as fenix brand, report much higher outputs and runtimes when used with rcr123a batteries. If you're using them in a surefire though you're good, any brands of concern will explicitly advise you, at least in my experience.
bottom line = they work, they save lots'o'cash!