I got my AirPort Express today. One of the reason being the bad speed I got on my MBA after ML upgrade. This was the results. My speed went from 4mb/s to 70mb/s. With BT on it was 2.5mb/s to 30mb/s. When I turned on all my other IOS devices (2 iPads, 2 iPhones), 1 ATV and PC desktop I use as PLEX server at the moment while my iMac is waiting to be fixed, it dropped back down to 25mb/s. Weird, but still happy with the improvement. Shouldn't I still be able to get 70mb/s if my other units are IDLE? Btw I am on a 100mbit fiber.