Hi, Glenn -
I was strictly an enamel user for years after acrylics entered the scene, I had read several remarks of how difficult they were for use, hard to get a good finish, dried in the airbrush, next to impossible to clean, etc. After seeing models painted with acrylics and looking great I thought wait a minute, at least try them, then judge.
I had an old Badger 200 single action airbrush, bought some Tamiya acrylic and their X-20A thinner, mixed up a small batch and sprayed some test patches on plastic sheet. I did experience some tip dry, but that's easily easily corrected with Q-tips dipped in alcohol, I was soon liking the paint really well.
I found cleanup to be remarkably simple and fast, their thinner works well, as does lacquer thinner, alcohol, acetone, etc. As to thinning primarily I use IPA 71%, but any of the other agents just mentioned work, I prefer the alcohol due to less unpleasant fumes and odors, and it's dirt cheap.
There are many advantages in using acrylic, fast dry, smooth finish, the model can be handled in just several minutes, but I still wait for at least an hour or so to be sure. It seems less likely to be affected by surface contamination, (skin oils, etc,) it sticks really well and I never experience lifting by tape removal as masking.
Vallejo sprays very well and looks great, my only issue with them is slow drying time and CLEAN UP. Alcohol causes Vallejo Model Air to form a gel, use that paint thinned with alcohol in your airbrush and be sure to have some food handy near your bench, you'll be there for a while cleaning up the mess. Even lacquer thinner is slow to clean up an airbrush when that occurs, but eventually it gets cleaned.
For thinning I start at a 50-50% paint to thinner ratio, then adjust it as needed following testing. Commonly I end up at 60-70% thinner to paint ratio, and the majority of my paint sessions are at 15-20 psi.
I'll bet once you give acrylics a try, you'll quickly be a convert.
Patrick