A:AnswerWe had a similar problem and it ended up being 2 things… 1. We had to better center the TV on the bracket by just sliding it while it’s mounted 2. Since we had to use like 5 small spacers and didn’t want to over tighten, it seemed like one of the spacers hadn’t finished settling. As we moved the tv a bit to be able to see the bracket better, the spacer dropped all of a sudden and the sagging was completely eliminated
A:AnswerYes, it supports pretty much all brands and sizes up to 70in I believe. Although if you have an LG G2 which it comes with it's wall mount in the box this one won't be flush to the wall obviously. But it can be used for sure.
A:AnswerI do not recall any tension settings. I think it comes pre-set. However they are very snug and so far have not loosened. The tv stays exactly where you put it. It never wobbles or tilts out of level. I have nothing but problems with my expensive Belogetti mount with these very issues but this mount has been awesome.
A:AnswerIt is black painted metal so I would think the surfaces would be protected. I do not know how well the pre-tensioned pívot joints will resist moisture.