This mount is a very good product; it's really heavy, durable feeling, the full articulation on the mount is very nice (particularly for our 75" Gorilla TV), and at this price for a larger TV you'll struggle to find anything other than fixed, or just tilt mounts.
What we didn't like; the instructions were pretty vague, just basic diagrams on a faded A4 sheet of paper. I would've appreciated more written detail, and/or a video to walk through. I had to guess at the order in which a couple of things went together, and ended up undoing my work once or twice as I started to figure out how it was meant to go – clearer instructions would've saved me a good chunk of time.
Something that'd really improve this product is including a template for screwing the wall mount into the wall. I spent a good chunk of time trying to do the holes myself but it's just impossible to hold the decently heavy mount with one hand while tracing the holes out with another, all while trying to keep it still and level. I had to get my wife in to help out and it was still a painful process. A template really would've saved a lot of frustration and measuring, which took us lots of time to do.
That said, at this price range and quality, it's hard to be too critical of the product. I'd recommend this if you don't mind putting a couple of hours (or more) aside to get it installed, and have someone who can help you do it.