Hi, I am a software developer and used AirDisplay 1 and 2 many years ago. Recently I switched to Duet with my MBP etc. But with the new MB, I had to switch back to Air Display due to the fact Duet needs to be plugged in. They have a attractive update bundle price and I got AirDisplay 3 for £4. Im pretty impressed. It works as well as I could hope for - some lag but not intrusive, not a major battery life drain (so far). Very nice. If you want a 2nd screen experience, I think it makes sense to go this way rather than Duet with the MB.