I use it myself, it's a dynamite value for the money. Don't worry about the "can't use the battery grip" comments, for video they just make a bad form factor even worse. Never seen a matte box or follow focus that would work with a grip. Unless you have a need to just bolt everything possible to your camera (and call it "your rig" I guess?) the 7100 battery life is great. Just make sure your baseplate allows you to get to the battery door.
If you don't use manfrotto QR gear you need to add a QR plate to it, but all my stuff uses their plate adapters, makes it easier to swap from steadicam to crane to tripod.