The battery grips made by Zeikos and Meike both perform the same in regard to the battery change over, which is to say it is the same way as the Nikon. I use the Meiki on the D7000 and Zeikos on a D90 and a Pixel on the D800. All work the same, very well.
My comments in the past about having the grip support a 70-200 was that I used mine by attaching the Black Rapid RS-5 to the lens foot, not the camera/grip. For best tripod results I also suggest removing the grip, any grip, because the mounting of a grip is not as stable as the whole bottom of the camera. There is a locating pin, and a attachment screw as the only locking points for a grip. My own experience with aftermarket grips has been excellent, no problems at all and gained a lot of benefits such as higher stability, lower shutter speeds possible with hand holding in the vertical orientation, changing a good handling body into a great handling body in either orientation, and as the least important on the battery miser D7000, additional battery life. The AF/AE L button changed to AF-On with each of the grips is in a better location and more sure in hitting than the AF-on buttom on the body. For those who use the AF-on for focusing, this is a welcome improvement over the placement of the button on the bodies. I never support a heavy lens on the sling strap by the body, it is risky having a single attachment point, but the main reason is because the whole assembly hangs is really unbalanced. I leave the sling coupled to the heavy lens when changing lenses and use the hand strap alone for camera/smaller lens hand use. That is a very convenient way to deal with a prime and longer heavy lens at events, no bag, just a small belt pouch for the prime or mid zoom like 24-70, and when the 70-200 is not mounted, it hangs securely by my side until needed to be mounted. Even a light camera like the D7000 with a heavy lens and a SB900 and some modifier presents a total package that is heavy and a potential stress on any one attachment point, regardless of who makes the grip. Good luck with the grip Peter, you will really like it if you shoot vertically as much as I do. Notice that being able to tuck your arms in tight to your chest means you can get a full stop lower in SS speed in vertical orientation compared to without the grip, using the overhand hold technique. It does, however make the whole package a little taller than a D3s and is hard to hide for stealth photography. Of course so is any good fast prime with its large front element that looks from a distance as a big eye looking at you which our brains are predisposed to notice instantly. Stan St Petersburg Russia