I agree with Johnny. The flat face bat create a bit of visual deception and look wider/bigger. Personally, having acquired a couple of flat face bats recently, I have fallen in love with them. The edges do seem to bit more venerable, but a few minutes of pressing them against the bathtub edges does the trick.
Also for those looking for a big edge bat, the flat face bats are a good option as the flat face bats will have 3-5mm bigger edges on them as compared with a bat with curved/round faced (like a Newbery or Salix). No wonder the likes of GN have made all their bats flat faced this year to deliver bigger bats for lesser weights.
I think it is difficult to get the correct pressing on the flat face bats. Have sen some where the middle just goes in like a crater and the edges become highly exaggerated. (not seen this yet on a Bradbury though).