Rechargeable lithium-ion batteries?

[iwong]

At my local camera store, I saw some rechargeable lithium-ion

batteries in common sizes such as CR123 or 2CR5 etc. Are they worth

the price they ask for? My C645AF is known to eat batteries for lunch

(expensive 2CR5's), and although I have the MP-1 battery grip which

takes 4 AA's, I'd like to have rechargeable 2CR5's on hand should I

don't want the bulk of bringing the battery grip with me. Leaving the

battery grip on also means I have to buy an expensive and big camera

bag to hold the camera.

 

Anyone has any experience with these rechargeable lithium-ion

batteries? The brand I saw was RUSH/JUICE (??) or whatever it was

called.