DZ versus Z3
I have the Delta Zulu as well as the Zulu 3 and still use both of them. The DZ has a nice app for custom tuning each side individually to your ears. Although that is a nice feature, I can't honestly perceive any difference in sound quality or tell any difference with the noise cancelation. That's not to say that the technology isn't working better (it probably is) .......... just that I can't tell.
I haven't been impressed with the rechargeable battery life and end up bringing along the AA battery pack anyways. Of course, they have the wired plugs as an option assuming your plane is equipped.
The security provided by the CO2 alarm is reassuring and seems to work well in the background without any added hassles to the user.
I do like the fact that the wires go into the same side of the controller allowing a more ergonomic fit into my side panel pocket.
I'm still happy with the purchase as I needed a headset for the other side. However, If I had purchased them to replace an existing ANR headset, I'm not quite sure I'd be as pleased.
I will say that I've used Lightspeed for around a decade and been completely happy with their Warranty / Service. That's primarily why I stuck with them over the competitors this time.