I bought my 50 1.2L in December of 2006 because it has much better “L” auto focus accuracy/consistency than the Canon 50 1.4 at wide apertures.
When I was using my Canon 1.4 on my crop camera for environmental portraits, it was frustrating to find that the three with the perfect smile weren’t always the same three with the perfect focus. I’ve never had this problem with the 50L.
The L’s only marginally sharper, color/contrast can usually be fixed in post, and bokeh is in the eye of the beholder. While there is not much of a difference in the FOV between f1.2 and f1.4, it can make a big difference in what lighting conditions you can shoot in, and if you’ve ever missed that perfect smile, perfect moment, or perfect light because the picture was not in perfect focus, then you will understand why Canon can get $1100 more for the L.
You can’t fix an out of focus picture in post and there are rarely “do overs” in photography. When the moment is gone, it’s gone.
