The one F25 '11 issue that I recall that was never satisfactorily resolved for some people was an issue with the steering rack at low speed. Search here, and you should find a few posts on it, which will let you know what to check for.
There were probably more battery issues reported for '11s, in part as a result of the way that F25s charge the battery to less than 100%, and in part because a number of F25s were not properly taken out of Transport Mode. The bottom line is that an F25 needs to be driven a bit of distance in order to keep the battery charged, and that a lot of short trips do not do that.
Other issues that come to mind for various years were window regulators, particularly on the passenger side, and rear washer pumps going crazy (bad JBE module) on a few 13's. There have been complaints about wind noise, probably more so in the '11 and '12 models.
I'm sure that I'm forgetting something, but those are the items that come to mind. Every year has had a handful of reports of lemons, which have been eventually resolved. Every year has an odd problem that impacts one or two people, but nothing pervasive.