What are the most air efficient paintball markers?

I am looking at getting an azodin zenith, as I understand that poppet valve markers are generally more efficient, but will the blowback in the azodin just counteract this anyway (or does blowback not really have an impact on efficiency)? Other than that, what are some of the most air efficient markers out there? Bear in mind that I will likely be using CO2 with an anti-siphon. Thanks!