The idea that one could 're-open' dried acrylics and blend them like oils really appealed to me. I started with this one:
San Giorgio - Winter dawn 7x8 inches
That was OK but I found that (contrary to the advertising blurb) there is just as much tonal shift when Atelier paints dry as with ordinary acrylics. In consequence, the more I painted new paint over dried paint the darker everything became. I then tried a looser, more fluid approach to the Crown Mines:
Crown Mines, Botallack 7x8 inches
This seemed to go better. The more positive and fluid I was with brushstrokes the easier it was to maintain tonal balance. Then this morning, I tried a Canada scene from an old pastel:
Bow Lake, Canadian Rockies 6x8 inches
I think this is beginning to work and I could paint on a small scale, en plein air with these paints. They do stay open longer and can be re-opened after becoming touch dry but the tonal shift that you get with acrylics is still there. Probably the biggest advantage is that it is much easier to clean up if you are using a dry palette rather than a Staywet type. I reckon that working really large is much easier with these paints than regular acrylics. I have heard that painting in humid conditions can be difficult because then Atelier is reluctant to dry but in the Rockies in summer I think I will be OK.
As far as quality goes, as with most manufacturers, the pigments used in reds and yellows are the ones to watch. I would not trust the Carmine in the Atelier starter set (I think it uses PR47:4 which is not very lightfast) so I bought their 'Permanent Alizarine' which uses PR175 and PR122 as my cool red and their Pyrrole Red (PR254) as my hot red. Both of these are Series 3 so a little more expensive. Otherwise all the pigments in the starter set are reliably permanent and all the paints are reasonably priced.