Hello All. I have a gig coming up where we need to fly really, REALLY high. Think 20,000' +. Obviously this won't be happening with a stock A8 as the performance tables stop at 10,000' and, even there we loose 10lbs of carrying capacity. I did a search and found some info on high altitude props but not much in the way of real world results. How high can I really operate an A8 with the HA props? Obviously minimal payloads, lightest batts possible and HA props. Are there any other mods that will make our chances of success better??