I like the more polished style A. Style B is nice, I like sketchy art, but something about it doesn't quite work for me, perhaps it would look better in black and white or something, I don't know, can't put my finger on it.
You could still use both styles and pick the one more suited to a particular work, or if you have an ongoing series, perhaps you can use style A for the regular art and B for flashbacks or other special panels.