After reading many reviews I decided to purchase the Zeikos grip but B&H discontinued it so I decided to go with the new Vello grip instead.
I think I might have made a mistake. The grip seems to drain power from my batteries VERY fast. I had the grip on camera with fully charged batteries and they were completely dead in a matter of days just sitting in my bag. I then charged the batteries (genuine Canon) to 100% and turned the camera off. I turned it on every hour or so and took a picture of the battery status menu. In 4 hours the battery power has gone down to 88% with power off and without taking a single picture.
What is going on? Is this thing defective or is there some setting I am missing?
I removed the grip and performed a similar test and the battery power has not gone down at all in 4 hours. The battery normally lasts a very long time so I was quite surprised to loose all the juice in a few days.
Unless there is a setting I can tweak I will return this grip and get a genuine Canon. Do people out there have any similar complaints about the Canon unit?