That's tough to decide. What drone do you have and where do you live and what's your normal lighting conditions? I live in Southern California and I've got the 4, 8, 16, 32, 64. I don't use the 4 and 8 much. If I only had one, I'd go with the 32 for when it's really bright outside. Most anything else can be adjusted with the camera ISO and shutter speed settings. You may not get the ideal 1/60 of a second but it will still be great video. I also have the histogram on the screen so I can get the balance correct. Sometimes the view on the phone monitor won't be the same as the video recording.