i have never really used a croix gun.
i seriously doubt they could actually atomize the high solids base coats and clears used on today's cars.

clear coats had mid 20% solids back in the early 2000's and at the time such high solids was phenomenal. today's low VOC clears are about 45% solids. for comparison purposes lacquer paint is about 5% solids.
i USE to have 4 accuspray guns in the mid 2000's. they work pretty good with low solids solvent base base coats. in the mid 2000's they upped the solids in the base coat to get it VOC compliant. they couldn't spray it properly so i sold them.

in my opinion the best atomizing spray gun for high solids clears is the Iwata supernova gun. nothing else is close.
i use mine to spray about 2 GALLONS a WEEK, sometimes 3 or 4 of high solids clear coat.
for water base coat most any manufacturer water base specific guns will do just fine. and yes water specific spray guns will spray solvent no problem. they have high purity stainless tips and linternal passages to spray water base coat without rusting.