I use Polly S airbru***hinner with Polly Scale, Testors and Tamiya acrylics in my Badger 200 with a fine tip.
One problem I encounter from time to time is that Polly Scale that isn’t “fresh” (i.e. has had the factory seal broken for some time) doesn’t always mix well with the Polly S thinner. When that occurs I think it with distilled water (which works, but not as well).
Your mileage may vary, check local listings, on approved credit, etc.