I’ve always had great results with Model Air but I do thin it a tad with Vallejo Airbrush Thinner and a drop or two of Vallejo Airbrush Flow Improver. Thinning paint to the right consistency varies from paint brand to paint brand. An art in itself and takes a long time to master seems to me. But you’re off and running in the paint shop dept. now, John @johnb. Looking forward to how it turns out.
By the way, any window cleaner with ammonia (like Windex) works well with removing unwanted acrylic paint. A little goes a long way. Dab the offending dried paint with a cotton stick tip, let sit for a bit and rub gently. Apply again if needed.
Be sure to clean your airbrush thoroughly because Vallejo paints tend to clog the needle as well as the paint cup unlike Tamiya acrylics I have found.