If I were going to go for a replacement for chemical lights, I'd recommend this one:

http://www.lighthound.com/Glo-Toob-Lithium-Green_p_570.html

Glo-Toob lithium is rated for scuba diving, and uses CR123 batteries, so it lasts 24-100 hours (depending on what cycle you use). Several different colors, and it has a good reputation on places like candlepowerforums.com.

Of course, it's a lot more expensive, but nearly unbreakable, and has the advantages that CR123s offer (availability, battery life).

That link is, in my experience, a very good source for flashlights and related items - no business interest, etc.

Dave