I shot Advance most recently on some cabinet doors for a bathroom, using a G15 gun on the Graco Merkur. Prior to that I had shot it with handhelds as well as HVLP.
It is a very nice finish. The downside is that it is a very slow dry, and even dreadfully slower cure. Great finish in the end, but in my mind if I am waiting that long in process, I might as well be using oil, which is still a little more desirable finish. Aside from that, Advance is a nice, and relatively thin, viscosity. It flows really nice through any gun.
With Advance or any of these ultra premium waterborne, it is not necessary to use any kind of extender (fluotrol, etc). If you spray to proper mil thickness, they lay down before they tack up, so there is no need to assist with leveling.
The real reason not to is because it messes with the dried sheen, which is very undesirable.