We looked at the KI desk for our new building and dismissed it as too complex and too noisy. It's a motorized system and you hear the gears and motor as the screen raises up. In addition, the screen sits pretty high so students can EASILY hide behind them.
On the other hand, a system like Smartdesks's flip-it (http
/www.smartdesks.com/flipit-kit.asp) is retrofit-able, simple (we're going without the keyboard tray - kbd/mouse fits in the monitor compartment) just relies on a simple hinge, silent, and gives all the flexibility of the KI system, without the noise, complexity, and view-blockage . . . and you can fit it to just about ANY desk as long as it's at least 24" deep. . .