25yd defensive shot? Self defense, HIGHLY unlikely. Defense of a loved one, completely plausible.
This subject came up at work. I provided the hypothetical - you are exiting the store, 20 some odd yards away your wife is struggling with someone who is trying to force her into a car. A friend says, "I back up from that door way, and go look at the sporting goods section for a few mor minutes. Unless someone is trying to help her, then I shoot that guy" As funny as that was, it is a realistic consideration. It might not always be YOU you are defending.
Honestly, I see no real reason for BUIS on a concealed carry pistol...... but I still wanted 'em mine. I went minimal though. I do not carry a full size spare tire, I carry a doughnut, and that is how I looked at my BUIS. I would've went with better sights, but (hopefully) I'm never gonna need them anyway.