Personally, I wouldn't use a third party substitute for the Canon BP series batteries. I've heard too many stories about third party batteries leaking, running too hot or not living up to the advertised run times. Then there's the warranty to consider. If a third party battery wrecks your camera for any reason you can't go back to Canon for that. I would, however, consider a battery brick and related connections/hardware from a reputable manufacturer such as Anton Baur. If your intention is to stay with a regular battery then go with Canon's PB 970, worth several hours of recording time when used on the GL2. The BP 970 lasts 40% longer than the BP 945 and is the same size.
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