Would not another factor be the topography of where you are?
I would not want to go off the end at, say, Madeira or Luton (RW 26), where there are "vertical drops" down to the beach or Vauxhalls factory (if it's still there!) but a few feet low at the screen height would not worry me quite to much!
Alternatively some runways have stacks of "emergency distance" beyond the end of the "official" ASDA.