I found this product to be an excellent addition to my photographic equipment, and use it frequently. I would recommend it to anyone, including professional field photographers.
BEST PROS: Comfortable and secure. If in a position where one might get distracted and may easily bump/drop/etc. a camera, the strong security function will keep your equipment in your hand. Too, the design and construction are very substantial.
CONS: It will take a little getting used to. It is a very different solution, so (though they are complete) the instructions seem at least unusual... because they are.
Like many things in photography, don't expect this grip to jump onto your person and be immediately yours. A little patience in the beginning will pay off big-time.