I love beautiful bokeh, so the 50L was my dream lens. But a lot of people will be just fine with the relatively ugly bokeh of the 1.4, so it may not be worth the cost. I think the AF speed on the 1.4 is fast "enough", but the build quality is very poor. (My 1.8 got banged around a lot and kept on ticking. The 1.4 took one little tumble and it threw in the towel.)