Mission Model Paints are now my go to acrylics after much experimentaction and heeding great advice. I have found that just using their thinner is the best way to go for trouble free painting, particularly, for detail stuff. I've struggled with their Poly Mix, too much tip dry for detailed painting (ie Luftwaffe mottling) in my environment (dry and high altitude (4,500 ft)).
With mottling I use at least 2:1 thinner to paint, at 8-10 psi (Iwata HP-CS .35mm). On larger areas and relatively fine lines, I thin 20%-30% per volume and spray 12-15 psi. I always spray a clear coat after my painting using Missions Clear Primer (30:70, primer to thinner) to protect the paint and prep for decals and weathering.
I do like to add some Poly when laying down base coats, but for detail painting, I'm not afraid to thin more and leave out Poly.
These are only my personal findings and they work for me. Bottom line is Mission Model Paints are the BEST water base acrylics out there and properly thinned they rival even Tamiya with lacquer thinner! Missions has definitely contributed to the advancement of our hobby.