I have never heard of any altitude related issues with the arrow's flight. I'm sure there would be some at extreme ranges - several hundred yards - but nothing that would affect the bowhunter shooting at responsible distances. The sucking wind part of the high altitude experience is a tough one. Even going from 6,000 feet, where I live and work every day, up to 11,000 feet causes some shortness of breath. For someone coming out from sea level, it would be a big deal. They say it takes about 30 days to become completely acclimated to altitude, so it ain't going to happen during a normal hunting trip. But the worst of it is the first day. Many folks experience a bad headache and have trouble sleeping. A couple of times I have wondered if a little oxygen wouldn't be helpful at night.