I bought two of these holders a few months back and I have to say, they really are very good.
They seem pretty sturdy and hard wearing, and they come with a memory lock you can attach to the stand you clamp them to, which - as well as offering extra support - allows you to attach the holder in the same place every time.
I've owned my two for a few months now and there is barely a sign that I've used them, let alone any damage... they really are built to last.
That being said, you could say you pay for this sturdiness in weight, as they are not what I would call light. However, I would much prefer to have tom holders which can do what they're made for, than use a flimsy, lightweight, alternative.