I have been using strictly Mission Models paints for a number of years now. I use the poly mix and thinner per their instructions and have been consistently successful. With the poly mix the paint evens out exceptionally well and seems more durable when cured. I find their acrylic much more forgiving and effective than other brands. I never liked Tamiya's acrylic and thought others such as Vallejo, AK, and Mig were ok, but Mission Models paints are better in all aspects in my usage.
I spent most of my building career using Testor's Model Master enamels. Mission Models is the first paint I've enjoyed using since. Now that I airbrush in a booth inside my house, this switch to acrylics has been beneficial. The one disappointment is, as others have noted, the short life of the poly mix once opened. I wish it were stable longer or available in smaller bottles (I only build around two kits per year). Other than that, I highly recommend the paint.