I have a question for you guys. Is there really a difference between 720p, 1080p and 2.7k? I have been filming with all of them and there is no real difference. The only difference I notice is that 720p is a lot more noisy than 1080p and 2.7k. But really, I can't tell the difference between 1080p and 2.7k. Also, I have tried multiple framerates and there is no difference.

From a distance you cant really tell that much but if you zoom in you will notice much finer detail the pixels are smaller with the higher resolution giving a better clarity to the finished product when viewed on high res monitor

What files are you watching, the ones recorded on your device (cache files) or the ones recorded on the SD in the drone?
What are you watching them on, as Hellsgate say, if the display resolution match the material the difference would be clear.

KedDK is spot on. Please check the original files of the SD card on the computer to see.