I've flown with David Clarks and Bose X in Cessnas, Pitts and Pipers. The Bose are more comfortable and great for medium noise reasonably insulated aircraft like modern cabin piston aircraft. They don't have a lot of passive noise protection and in high noise aircraft the ANR can't cope.
In high noise aircraft like a Pitts or alike with almost no insulation, the DC win as the passive noise cancellation gives some protection that the Bose ANR can't cope with.
Perhaps the Lightspeed Zulus have the best of both worlds, I haven't tried them but am keen to.
By the way, I sold my Bose on e-bay. There were about 12 pairs for sale, there were no Zulus for sale. Perhaps that is telling in itself.