I've used the entire range of their products and so far have found the composer PRO to be the best bet. The focus ring is much more refined than the basic composer.. and well, I quickly got annoyed with the muse and the control freak takes too much time/effort.
They truly are a lens that you either love or dont. I'm the prior. easy to use creative aperture discs, get exactly what you want in focus and with the double glass optic they are quite sharp! Or you cant get really soft images with other optics too.. pushes me to be more artistic and think through each of my shots. Unlike the massively automated AF lenses I normally use.
Anyways, I shoot with it frequently..