It's what I use anyway, but I haven't used Humbrol Acrylic since I started using it. Works with Tamiya and Vallejo. Btw the cockpit and wheel wells on the Tempest are brush painted in Humbrol matt enamel, I still like a brush sometimes.

Plan old 70% Iso Alcohol is ok for thinning acrylics, and cleaning your air gun, but it's not the best solution for either.

Used straight to thin acrylics lets the paint dry way to quickly, causing all sorts of issues including clogging the gun's nozzle. You really need to add a few drops of retarder to slow down that process. I use Tamiya's X20A which is basically 50% Iso Alcohol/Distilled water, a retarder, and a few other things. Works a lot better, but isn't perfect either. If you use a paint booth, or the oder isn't an issue, cut the acrylic paint with lacquer thinner. You actually end up with a smoother surface as it dissolved the paint particles so they're a small dia.

As for cleaning my air gun, I stopped using Iso Alcohol. Works ok, but takes forever to get all the paint out, and dried paint in the nozzle is as time consuming issue. Instead I clean it with Lacquer thinner. Switching colors I just shoot some LC through the gun till it comes out clear, then change colors using a different bowl. I don't always take my gun apart to clean it, as running LC through it does an excellent job. I do have to clean the paint bowls, which takes like two min each.

I can only speak about the ease of cleaning for my Paasche 1H single action external mix gun. That's all I've used for over 40 years.
Joel

Not to hijack this post but I did post my question about Humbrol acrylics and asked what to do to thin/clean up. I tried everything and in each case the paint just clumped into little tiny gooy-sticky-stringy lumps. I was worried I had so many chemicals in my room that everyone would be thinking I had a meth lab going . A long stint in the sonic cleaner with acetone seemed to at least cleared up my AB.

Try getting a compressor from Harbor Freight. They run about $75 for a decent one that will do all the things you need, including running a air gun to remove the lug nuts from your car wheels.

Use a small jar with a tight lid. fill just enough with lacquer thinner to cover the largest part you plan on putting in the jar for cleaning. I usually put the needle & cone in separately from one cup at a time, and swirl for a min or two. Then remove the parts, and clean with a Qtip, pipe cleaner, and paper towel all soaked in LC. Works perfectly.

One thing to remember, don't clean any plastic or rubber parts in LC, they will dissolve.
Joel