I have one of these grips and I've been using it for the past few weeks. I got mine cheap because the original owner was suffering the battery drain issue (if you're not familiar with this, search the reviews on Amazon, et al for this grip; it's a very common complaint). I wanted a grip because I have big hands and want the ergonomics of a grip so the battery issue, really, is immaterial to me. I insulated the data port on the grip so it really doesn't "do" anything but provide a better, more ample gripping area. If I wanted I could store an extra battery in the grip, but I don't; I leave the grip empty for the weight savings.
The battery drain issue is very real in my experience, however. When testing the grip I found I was losing charge at about eight or nine percent an hour. This was with both the battery grip and camera body turned "off" and sitting on a table. On the upside, the build quality of the Pixel Vertax grip is great. Really, really good and I mean right down to the last detail. I tossed the previous owner a few bucks knowing about the battery issue because, again, I want the ergonomics the grip provides, so I'm a happy camper. Had I paid $90 for this, along with the battery drain issue, I'd have been pretty pissed.
Edit: Amazon Reviews HERE for anyone who might be interested.
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