We use the Finishline III gun for both base and clear at my shop. I have seen the Iwata and Sata guns and have never been impressed with them. You have to move too slow with them.
This is a 2010 Challenger where we used the Finishline for both the base and clear. The graphics are air brushed with clear coat applied with the Finishline III over them.
Frank Cox
Cox Custom Cars