Charge vs price
Crutchfield Customer Review (What's this?)
The Canon batteries cost more than other brands, a lot more, but they last longer. I've tried several other brands that have mwh ratings as great or greater than the Canon's, but they never actually last as long in the camera as the Canon batteries do. It's a trade-off between how many batteries you want to juggle and how often you want to change them vs. paying a higher price for the Canon batteries.
Pros: Last longer than other brands
Cons: Much more expensive than other brands