I haven't tried any of the non-canon battery grips, but I can quickly comment on the canon one if you're interested.
It works flawlessly! However, I very rarely use mine. Basically, the battery life of one battery is way more than I'll ever use in a single shoot, or even 5 shoots. Carrying a 2nd battery as a backup is thus better than the BG-E3 for battery life. When your battery does run out, simple switch it. You can charge your dead battery when you get back home. With the BG-E3, when your batteries die (it holds two), you have nothing to switch them with. Thus, you actually end up being MORE worried about battery life with it in. That, or you end up carrying a THIRD battery.
In terms of replicating the controls for shooting in portrait, the BG-E3 works great! I used mine for a while, but then one day I took it off because it is fairly big and heavy and realized that it's really not any different to just use the normal controls. Since then, I have very rarely put it back on.
Pro: replicated controls
Cons: worrying about batteries, big and heavy |
