Yes, I am and I love it.
Works extremely well. I first used MM about 5 years ago but moved to Mediabrowser because the MM Media Center plugin was so kludgy back then.
My main gripe with MB is that the interface is not as consistent with Media Center as I would like. So I decided to give My Movies 4 a chance and liked it so much that I uninstalled MB.
It is not as customizable as MB but it does what I need it to do. The collection manager is a great feature once you have figured out how to stop it from overwriting the locally stored cover images.