I bloom the alba (fma. sandowiae) better and more frequently than the 'normal' form. In fact I have two alba in bloom right now... The one in the picture was awarded AM/AOS last year. It is a clone that Sam Tsui was using fairly frequently in crosses, and I've put it on a few things myself.
I don't bloom the dark forms often enough to know if it is good or not. To me it felt a bit small (although well proportioned). I very much like the color and the petal shape is excellent. My photography is less excellent, so you might not be able to tell.