I bought this for my mom who moved into a new house that had a pre-existing over the fireplace mount, but it was up too high for her to feel comfortable with the viewing angle.
The quality was great, install wasn't too difficult, and we were extremely pleased with the outcome. I would definitely recommend it to anyone in a similar situation.DynamicMounting.com
Here are some pics of what ours turned out like
(Sorry about the cell phone pics, that's all we've got right now)
(The TV is a 55" if that makes a difference to anyone)