I got one of these recently also, new.
As discussed endlessly elsewhere and as I expected, using spyder lenscal I can confirm it does backfocus when you are within ~1.5m of the target and not wide open using center point focus. Canon could have avoided the whole backfocus controversy by increasing MFD, but it is nice to be able to shoot close & wide open. If they increased MFD, you would lose that option. So, I think it is better just to know the lens limitation and shoot accordingly. Sort of how you wouldn't bring an 85mm f/1.2L to a sporting event due to the slow focusing, if you are going to take close ups with the 50 make sure you are wide open (or sometimes using outside AF point works).
But, otherwise I have really enjoyed this lens. It has a special look to it, and the 50mm focal length is huge for indoor events in particular, as in my opinion for indoor events 35 a bit too wide, 85 a bit too narrow.
So, while I can see this lens does have a learning curve and is not for someone who just wants to point-and-shoot without worrying, I think it does bring something special to the table.