I once flew with a friend's DC 13XL and was immediately hooked. One problem though: it costs $600! I ended up buying the Softcomm C90 (
www.softcommheadsets.com) which does essentially the same thing for half the price. The electronics are not as sophisticated as the DC ones, but the end result is the same.
The only thing that gets filtered out is low frequency noise, so don't worry about the stall warning horn, I find I hear it better with the ANR on.