Your SW 457 is a great 45 carry pistol. The full size Beretta 92 is also a great pistol but is longer in the barrel than your 457 and thicker in the grip. The grip length is about the same with a mag inserted as the 457 (I own both). I also have the 92 compact which has a shorter grip and barrel than the full size 92. I prefer the shorter grip of the 92 compact for carry. So the best thing to do is to get your hands on a full size 92 and see how it feels as a carry pistol. If it's not too big then go for it. Good luck.
Happy Thanksgiving- oldandslow