I haven't had problems as of late with them busting out, but then again I do squats when I first got a 6 order set and busted two right out of the bag.
I literally wash mine 10-20 times, tossing 3-4 shirts in every load of laundry we do. Someone on here suggested a salt water bath in the bathtub, didn't notice much difference but I was already 15ish washes in.