I use Testor's Air Brush thinner for thinning paint through my air brush only. For clean up I use mineral spirits and lacquer thinner. I once had a bad experience with mineral spirits and Model Master Zinc Chromate. Maybe it was the operator or I just wasn't holding my mouth right, but I've never had a problem with the Testor's stuff. The half pint can lasts a good while and it's worth it to me for the piece of mind. For what little mind I have left.
Regards,
Michael B