I been running into issue where unlike the first gen h520 st16s controller which uploads log files with out any issues. The st16e will error out and not upload any of the log files that is produced from each flight. So far that is the only negative issue I have had with the second gen h520. Just did 9 flights doing some photo and video shots at the request of my friend of his house in a subdivision outside of Perrysburg Ohio. All green no problems. used e30zx and e90x payloads.