I think that if a nighttime attack was to occur that the ability to attach a tactical flashlight to the handgun would be a plus.

Here is an interesting article that illustrates that most any decent gun-in-hand that you can use well (and a flashlight) in a somewhat proven manstopper caliber beats no gun at all - and quite nicely in this case despite what armchair theorists may say - at least this guy, if not ideally equipped, was obviously somewhat in the ballpark with caliber and ammo and had opportunity to use the extra capacity:

Quote
GLOCK STOPS A GRIZZLY ATTACK
as told by by B.K. - Anchorage Alaska

My wife and I did not think there was a burglar in the house, rather, I was sure that our cat was on the kitchen counter knocking things over.

It was 2:30 a.m. I used a Surefire 6P flashlight to illuminate my hallway (held in my left hand at the same level as my gun in my right hand at eye level). It all happened so fast.
There was a bear coming my way. It was at about 7 paces when I rapid-fired 10 rounds at center mass. Nine bullets connected, 4 were fatal wounds.

The gun used to take down the bear was a .40-caliber Glock. The hollow-point bullets performed as advertised.

Some reports are saying that I just stood there with an empty gun. Not true. I ran to my office upstairs (the bear was downstairs where my gun safe was) and grabbed my spare magazines. I quickly returned to the stairwell after dialing 9-1-1. Once the officers were on site we worked together to ensure everyone's safety. They were cool-and scared-who could blame them.

As it turned out, the .40-caliber 180-grain Corbon hollowpoints at 1300 fps were enough to take down a bear in short order. A lot of folks were saying that I got lucky or that I should have used a bigger gun. Some even said I should have simply fired a warning shot to scare the bear out of my house. I believe that skill beats luck every time. For years I trained with local IDPA and learned skills that saved my wife and myself from being mauled in our own bedroom! I used the gun I had at hand.

Lessons learned: Keep a gun of at least .40 caliber or better in the room that you occupy at all times; use real bullets, not target loads; train to the point where you'll be ready for anything.
Glock AUTOPISTOL magazine 2008 "Tales of the Gun" pg.39

"We deal in lead - friend"