I would like to start spraying my projects. Primarily water based poly and lacquers. I currently have a 21 gallon sprayer that is rated for 4.9 scfm @90 psi and 7 scfm @ 40 psi.
I was considering a conversion gun or a Fuji/earlex system. Minimum two stage. Cost of course is always a concern. I don't want to spend more than 600. This will not get heavy use. I would only be using 8-10 times a year (hopefully more)

What are the benefits of one vs the other?