In my line of work, we spray a lot of abrasive metallics. We use stainless steel needles and tips, and replace them every 6 months. This stuff would be really hard on an airless rig, the pump seals and guns would take a beating.
The Graco Delta Spray is a great gun for this application. It has a replaceable needle tip ($8 piece of nylon) that keeps them running almost forever. You can get them in pressure feed, gravity, and suction. The DeVilbiss gun is really great as far as a nice finish, but the needles and fluid tips are fragile and require frequent replacement.
I am going to use my pressure pot setup and one of my Graco guns when I paint my deuce.
MCLB Albany uses a Fluidics 2K mixing system. It has to have pump seals every 6 months, but holds up well. They tried the Graco Precision Mix units, but they couldn't take the abrasives. They spray over 1000 gallons per month per booth, so their equipment takes a beating.