Each of these keyboards arrange the keys in a grid, rather than in offset rows like typewriter-style keyboards. The idea is that a grid, in which the keys are aligned both vertically and horizontally, requires less finger movement and reaching.
Beyond the grid arrangement, though, the two keyboards are very different.
The EZ-Reach arranges the entire keyboard into a concise rectangle, with the often-used Enter and Backspace keys in the center, and embedded cursor control and number pad keys. One very important benefit of the compact design is that the keyboard is not as wide as a normal keyboard, allowing the mouse to be kept within easy reach.
The Contoured Keyboard uses a totally different approach, placing the keys into two “cup-shaped” keywells into which your hands naturally rest. There are separate key blocks for each of the thumbs. This design is considerably wider than the EZ-Reach, but still relatively narrow compared to a regular keyboard. It does take up more space depth-wise.
Svensson preferred the Contoured Keyboard, finding it “very comfortable”, with “minimal movement is needed to hit each key”, and “the wide separation of the keypads mean the arms don’t need to angle in.”
I have not tried either keyboard myself. I did try a compact keyboard once upon a time (with a normal key layout rather than the grid of the EZ-Reach), but I didn’t care for it. It felt like my hands were too close together, resulting in the wrists constantly needing to be held at an angle. The Kinesis keyboard looks very promising, and I may give it a try next time I’m in the market for another keyboard.