AirPort Extreme A1521 Repairability Score: 8 out of 10 (10 is easiest to repair).

No proprietary fastener funny business over here. The Extreme uses Torx screws throughout the structure to keep its act together.

Disassembly is pretty straightforward, and modular components are used throughout.

No glue (except for a small dab used for the status LED) is found inside.

The opening procedure requires a bit of prying that may slightly damage the case if the user isn't careful.

You'll have to disassemble a good portion of the device in order to clean the fan.

Some of the connectors are super-small and can be prone to breaking.