I finished installing the ANR DIY kit in my H10-13.4's. Doing five flights in the Pitts tomorrow so will see if it makes much of a difference. I did plug them in to make sure they work and they immediately cancelled out ALL the noise in the hangar. However the intercom was a little more tinny or artificial in its sound.
If these don't work to well then I will drop the coin for a set of Bose. I have used a set of Bose previously in the Pitts and they seemed to work very well for me. Go figure... Just trying to save myself $1250 by trying out the ANR kit for the 13.4's first. If it doesn't work to well I guess I will always have an ANR set for my Pax...
Cheers
CB