I have bought a few of these. Haven't used them on a model yet, but i have done some practice painting with them. The end results are very good IMO.
I watched a few different YouTube videos on using them first, which helped set the starting point, then I tried to find the sweet spot for my setup. Unlike what the literature says, I had a hard time spraying right out of the bottle, and do prefer using the polyurethane additive. Someone suggested a premix of 10 parts thinner to 1 part poly then using that premix to thin the paint at a ratio of 6 parts paint to 4 parts thinner for base coats. This seems to work well for me. But that is all personal taste. Remember, they are acrylics and with all water based acrylics, thin coats work best building up the coverage.
Paints tend to be personal taste, I like these. Others may not, but give them a try and see what you think.
Mike