I have never seen any advantages of a hole in the handle, so I have kept away from them. Seems like you could only get em via custom stocks years ago, but I have now noticed them off the shelf as common.
It got me wonderin......, so that is why I asked. Benelli was even pushing em on their turkey shotguns. I turkey hunt (Benelli super black eagle), and it would be even more of a detriment for me on a turkey rig.