I guess my real question for all the 50 mm L-series users out there was: is the 50mm 1.4 not enough.
I did exactly that a few years back...sold the 50L and kept the 50 f/1.4 which I also had and still do. This is not
to say that the 50L was not exceptional; when the AF nailed the subject it was tack sharp and the bokeh was sweet. However, in my specific lineup it was clearly an extravagance with 35L and 85L.
Mind you, in the interest of full disclosure, in the last month, I did go through a pathetic (Gollum-like), gear-driven, fever to get the 50L back in my collection... but it would have been a luxury; my concerns about it from the first round would have resurfaced once it was in my hands, and it is highly unlikely that I would have suddenly found more use for it than I had the first time around...
So, if the 50L truly fits in your line up, and you have the funds for it, of course get it... only you can make that call.