^^Been trying to break mine in for two weeks now and they are still stiff. I've been working in them (stringing racquets and walking around my store), taking to the grocery store, doing drills in them, etc and they are still stiff (after two weeks). I will keep at it but I am going to order some GR5s because I prefer out of the box comfort.
(2) Wilson ProStaff 95S with leather grips
(2) Wilson BLX PS90 and (2) Wilson 2014 PS90