I just had their mod kits for the N64 and GameCube controllers arrive.

The N64 controller install is basically flawless and impressive, the GameCube controller mod i don't really like the charging cable/port, they send you a 10cm long cheap cable, and his brings me to the next point, its a huge risk using these modkits, I've got both of them working 100% on emulators on PC but they aren't as easy as just buying controllers from Nintendo directly.