My current Bose headsets are second generation, meaning not the current X version, nor the intial version that Bose delivered late, and later recalled, I remember. My wife and I slightly preferr the Bose, having used two different generations of ANR headsets from Telex, which cost much less than Bose. The Telex are (we kept them for passengers) just as quiet as the Bose, but a little heavier and not quite as comfortable. Service from both companies is very good.
One irritating fact about ANR headsets: both Telex and Bose suffer from extraneous electrical noise, such as from nearby-radar, or solid-state-dimmed panel lights when they're on at night, or solid-state voltage regulators. Your shop tech will roll his/her eyes and try to talk you out of an expensive attempt to ground and shield and filter all the stuff in your aircraft.