ErgoDox EZ vs Hassium Pro 108

You can map any key to any position easily using a simple GUI, including making hardware key layers. And, since the firmware is open source, you can modify it to do anything you want. Many of the hardware components can also be altered/replaced by equivalent parts.

You can arrange each side of the keyboard to match your hand positions. Helps keep your body straight and improve your posture.

Because of its split design, the ErgoDox lets you optimize the positioning of its halves according to what's best for your body shape, even if you have broad shoulders and large hands.

The ErgoDox has an open design, so if you want to modify anything at all, you can fork the Github repository.

There are more keys which are easily accessible for touch typists than on common keyboards.

Unlike other keyboards, like the Lexmark M15 and Cherry G80-5000, where the only action performable by the thumbs is punching the spacebar, ErgoDox has extra keys placed near the spacebar, within thumb reach. This prevents the thumbs from being a bit redundant.

Almost all the keyboards have a small row offset (for example, on a standard QWERTY keyboard, the A key is not directly below the Q key. On the ErgoDox, this isn't the case: keys form straight columns. Together with the movability of the two parts you can stretch your fingers straight on, not slightly sidewards. This helps with touch typing, since you just need to stretch your fingers straight onward to reach the key above, rather than stretching it onwards and sideways.

Because of the nature of ErgoDox, within an open source community, there are advancements in firmware being made continuously.

With most programmable keyboards, you have to use their software in order to save and reuse your customizations. Using such keyboards on other systems "degrades" them to their default setting. Since with the ErgoDox the settings are saved directly on the keyboard, no matter the system where you're using it, your macros, tap dances and layers are always available.

The Ergodox doesn't allow you to reach over the centerline to hit T and H with a single finger, or whatever other bad habits you might have. The split design forces you to keep your hands in the right position.

The pre-assembled version offers an extensive 2-year warranty, provided you haven't taken it apart or physically broken it.

You can put the keyboards together, making it very easy to carry around.

This keyboard uses Cherry MX switches, which are premium switches: long-lasting and solid. The Blue, Brown and Red varieties are available.

Light can turn on and dim-off on a per-key basis and there are laser beam, ripple explosion and breathing effects available. These affects can be self-programmed.

Both white and blue LED backlighting is available.