The ErgoDox EZ earns a 10 out of 10 on our repairability scale (10 being the easiest to repair):

Parts that are prone to wear, such as key switches and cables, are modular and individually replaceable with off-the-shelf components.

The product comes with a specialty tool, which is not necessary (but very helpful) for repairs.

The enclosure is held together with standard Phillips screws. No adhesives or clips are used.

The manufacturer provides repair documentation on their site.