My husband and I, besides doing professional photography, also do videography, and we have professional video camcorders that we use on a job. These batteries are what power our camcorders. I think we each have about six of these batteries for our respective camcorders.
Each battery is supposed to have eight hours worth of power in it when fully charged. I can't attest to that, because I've never filmed for that long at one time, and so my batteries have never run out of power on me. I am also in the habit of recharging after every use, so they have full power when used again.
The Ultra High Capacity battery is very durable and reliable. Our batteries are model BP-945, with 7.2 volts each. They have given us good service for a number of years. In fact, hubby and I recently had to buy a few new batteries because our older batteries went dead and wouldn't charge anymore, and they lasted from 3-5 years before this happened.
I would recommend these batteries to anyone with a digital camera or camcorder that requires this type of battery.