Shuttle has tested and recommends these 3 Mini PCIe WiFi cards for the SX79R5, SZ68R5, SH61R4, SH67H3, SA76R4 and the XH61V models:
1. Intel Centrino Advanced-N 6235 WiFi and Bluetooth
2. Intel Centrion Advanced-N 6230 WiFi and Bluetooth
3. Realtek RTL8191SE WiFi only
Mini PCIe Internal WiFi card kit
These were all tested with Windows 7 only. We will have to test compatibility with Mac Lion, Mountain Lion.
If anyone knows if drivers for these cards are available for Lion and Mountain Lion, please let us know in a comment.
Posted by cinlortech 
CinlorTech's Blog 