I've been flying a few months now. I was really trying to be cautious and decided to go with 3S batteries for all of my birds. I now have 4-5 birds that I outfitted with 5-6 batteries each, 3S of course. After doing a bit of research, I think I made a bad investment. I found this review and a few other similar ones to come to this conclusion. You decide what's right for you.
Jerry
Jerry