I use a fluid bed only for base colors. If you do multi-color the fluid bed at that point will be useless. If you want the quickest and cleanest and most economical way to paint jigs. Then powder paint is the way to go. If you go the airbrush route there is a lot of initial cost. Using water based paints like Createx, you must then clearcoat all of your jigs. If you use lacquer paint, then no clearcoat is needed. However, you must have adequate ventilation, a respirator, a spray booth with a non-combustible overspray extracting system. I use powder paint and Createx. I powder paint a basecoat on some special jigs and then I can spray it with Createx, heat set it and then clearcoat. There are many things you can do with an air brush even with water based paint that you can not do with powder paint. There are many ways to make some really creative jigs out there. Just my two cents worth.
"Practice, practice and more practice and when you think you're good, practice some more." circa 2006 Cadman