The support acts and is massive. Whether it withstands the above 120kg, I do not know. But that's completely irrelevant. my modern 42 "LCD weighs without walking just one tenth.
The adjustment possibilities are very good. Horizontal with a massive double joint (parallelogram) very solid and gelößt stable. Depending on the display width of the swivel range is outstanding.
Vertical not quite as flexible - but this area is normally fix and adjust once.
When attaching to the wall should not tighten the screws completely equal. By design, form the moving parts is not necessarily a right angle. The horizontal one can compensate when tightening.
A "correct" level should be preferred over plastic toys.
Especially in terms of the price, the task can not cope better.