I've been spending some more time with the 50mm 1.4 lens lately--it's size, wide aperture, and focal length make it a convenient choice. But the slow and inaccurate autofocus continues to bother me. To try to get around this, I've begun focusing manually, especially in low light. The upside is that relying on manual focus has made me better at predicting the focus distance. I'm nowhere near perfect but my success rate has been improving. Knowing the focal length well, this has allowed me to compose shots fairly accurately without using the viewfinder.
I'm pretty happy with the result here. Using autofocus and composing through the camera, it would be difficult to get a picture like the one above.