Environment speedpainting

A piece I created today. Took me 40 minutes. I'm still a little confused by all these custom brushes in photoshop. Till recently I painted only in gimp using basic round  (mainly soft) brush like 95% of the time. I downloaded 30 day photoshop CS3 trial and some custom brushes of known artists. Now I test them and sweep out those I'm not comfortable with to keep it as basic as I can.