I previously used an Aztek A430 double action, but based on my personal experience with it, now recommend against them, not for performance issues but reliability issues.
For the most part, it did paint reasonably well. When it did not, I could fairly place the blame on my own lack of experience, i.e. operator error. Unfortunately, after a relatively short usage life, the body would no longer spray, necesitating warranty replacement and the loss of use during the three week turnaround. I have no idea what I could have done or not have done to have caused the failure. Certainly I followed Aztek's cleaning instructions explicitly after every use, thus I cannot excuse the body's failure to simple operator error.
I have heard a lot of other comments form other Aztek users both in this forum and other modelling forums who have shared a similar experience to my own. As a result, I consider the Aztek to be an unreliable airbrush.