I currently have two batteries and one charger and want to pick up another, along with an additional charger. I sat down and went through the fly, charging and wait times. At first I thought it would be a simple matter but, at least for me, it was a little more involved. I know that flying and charging times are always going to vary. For my purposes I used a 20 minute flying time and a 1h30m charge times. I think these are pretty standard when the batteries are flown down to a 25% - 35% charge amount. Also, this does not consider any wait between flights. From what I read from DJI you should allow a little cool down time on the motors between flights. It would also take 5 – 10 minutes to get the drone back into the air. Three Batteries, all fully charged: Fly for 1 hour Wait 50 minutes Fly for 40 minutes Wait 50 minutes Fly 40 minutes Wait 50 minutes At this point it’s rinse and repeat. So with 3 batteries and 2 charges you are flying for 1 hour, waiting 50 minutes and then it’s a steady 40 minute fly with 50 minute wait. This makes sense as it's an 1h30m less 40 minute fly time (2 batteries charging at the same time). With battery swap time you really might be only waiting 30-40 minutes every hour. I think 3 batteries with 2 charges is the sweet spot for the money and waiting time.