The 8bitdo are wonderful controllers, albeit a bit small. I have the NES30pro which doesn't include the rumble/nfc/ all that, so it's a bit smaller, but I've tried the one with it (can't remember the exact name) and it's way more comfortable, bigger grips, and fully functioning
People seem to be missing what the 8bitdo device he's asking about is. It's not to connect their controllers, it's to connect other controllers (as well as theirs if you aren't using something that they connect to without it)