I think when you use those holes to mount 4 sq. box for receptacles they can be a bit flimsy(if plunger isn't used)and can be irritating when drywall is cut bigger then the ears of the device. I have in the past knocked out 2 of the 1/2 ko's and screwed using fender washers, seem to be a little more secure being in the middle vs. the front IMHO. Not time efficient, but neither is trying to fix a loose box on trim out.
