Canon 70d Battery Grip

[Luke345678]

I posted this in the Canon accesories thread as well but it hasn't really been seen over there. I apologize for posting this twice but I just wasn't getting any answers in the canon thread.

Hello there everyone,

In about 2 months I will be purchasing a Canon 70d. I would like to pick up a Battery Grip as well along with the camera but I'm not sure if it is okay to go for an off brand battery grip.

Here's what I was looking at.

Canon battery grip
Amazon.com: Canon Battery Grip for EOS 70D Digital SLR Camera: CANON: Camera & Photo

Off brand battery grip
Amazon.com: NEEWER® Battery Grip Holder For Canon EOS 70D Camera DSLR Replacement For BG-E14: Camera & Photo

Thanks,

-Luke