I've used the 850's in the Dash 8 and Citation 550-560. I find the audio to be OK and the noise cancelling works well enough. The Dash is more vibration than wind noise, that might have something to do with it. The Citation isn't really quiet, but I imagine it doesn't have the wind noise problem that faster airplanes. 262 or 292 indicated down low and .73 up high for the 560 (.60 in the 550)
They've been decent for the cost, but long days(6+hours) makes the outside of my ears hurt,especially wearing sunglasses. The ear seals tend to fall apart in a few years, but they are a simple fix. It's $20-$30 to get the seals.
I might replace them with something else once they break, but I've been happy with them. I have Lightspeed Zulu's for back-up from my instructing days. I love those, but just too bulky to have in the kit and wear, even though they are comfortable. Not a fan of in-ear style.