I am on my second of these trays, because I had to leave one behind at a previous workplace. This is my kind of keyboard tray because I am short, I type at the -15 degree tilt (most keyboard trays have never heard of this), and my mouse tray needs to be at a level angle not at the -15 degrees. On most keyboard trays, if the keyboard is even close to where I need it, then the mouse is sliding on to the floor multiple times a day. The 3M mouse platform can be tilted however you want, but there is a wonderful guide so your mouse won't fall onto the floor. The other amazing feature of this keyboard is the fact that the whole keyboard can be slid left or right. I would go so far as to say that if my company wouldn't buy me this keyboard tray, I would spend my own money. Keeps carpal tunnel away.
When attaching the keyboard platform to the arm with the included screws, it didn't feel quite right. It felt as if the screw was really only threading into the paint, not into threads in the metal.
Here I am about 6 months later and two of the screws loosened and fell out. Oddly, two of the other screws seem to have tighter threads, so moving it around I've been able to secure it a bit better, but the whole thing is still wobbly. If I continue to tighten the screws further, I fear they'll just take out the rest of the mating surface.
I've contacted 3M through the contact link on the site. If they are able to help and resolve the problem, I'll gladly update the review. For now, I can't recommend it.