I downloaded Sai recently, a friend adamantly recommended it for digital painting so I thought i'd give it a go, and did this;

Please give crits if you can, something about the arms/proportion looks wrong but I cant put my finger on it
I don't do much digital painting at all, except for textures to go on 3d models, but when I have done digital painting it's been in Photoshop
Compared to Photoshop, Sai somehow feel so much better
It's really fast, responsive, feels really natural, you forget you are using a tablet at all so quickly,
as opposed to my experience with Photoshop, where it's a constant battle of man vs machine