I use the bose and have loved them. I also used the david clark x-11 for a while not bad once you where able to get a good seal but by that time the battery wouled die.

I too fly the Brazilia; I have David Clark X-11's. They are pretty nice. Used the Bose before and thought they were alright. Didnt like how the earcup fit around the ear. The X-11's are comfortable and light, good fit. recomend going and trying each pair on. Some places will let you do a trial use.

A caution with the Bose QC2's... some of my fellow pillot users have had problems with the Ufly Mike getting lose after being used for a while.

The batteries in mine last 30 hrs. Both of you guys must have had a bad batch. I used to sell them for a pilot supply store and when the X-11 first came out there were alot of returns for those reasons. the ENC modules in the earcups were going bad. We just sent them back and David Clark fixed them and never had any complaints after that.

I would highly recommend the Bose. I have over 3000 hours on them, 1800 of which came from flying the BE1900 part 121. Once the 5-year warranty expires, all repairs cost $175, no matter how extensive (the one con, in my opinion).

I tested the CA at Sun-n-fun, and liked the product, but never flew with a pair. If you feel they would handle the on-off-on-off of 121 ops well, that may be a good way to go (no batteries to change).