Really good examples of this lens in your review. My concern about the 50L is this: At 2.5x the price of the 50mm f/1.4, shouldn't it give at least 2.5x the performance improvement? It doesn't, especially at wider apertures. I would at least expect it to be sharper than the f/1.4 wide open, but clearly it is not. Where the 50L really shines, though, is the quality of the bokeh shooting that wide. The 50mm f/1.4 can't even touch it. In that respect, a photographer is better off getting the 50L if they depend on that kind of background blur.
Having said all of that, I would in no way turn one down if somebody wanted to give me one.