He has valid points in his situation. Having a pistol with a light and suppressor will be very easy to maneuver when clearing a house. I have HK USP and a Mark 23 45 ACP, both with lights. However, I prefer a Carbine (Noveske Thunder Ranch with an Aimpoint T1), myself. More firepower, greater effectiveness, longer range, and greater accuracy. It can be fired one handed, if necessary. Follow up shots are much easier. Multiple attackers can be handled, if necessary. It doesn't have an issue with overpenetration as much as a pistol or shotgun.
A shotgun is great but maneuverability is more limited and really requires two hands. Sure you can mount a light but unless you have a clear shot, you'll be creating massive damage in the house - especially if you miss under stress. Problem is what type of spread you're dealing with, at a certain distance.
No single answer is going to fit every single person's household. Not every scenario will fit a single answer, either. Not to try to clear a house, like you're SWAT or Special Warfare, just ensure safety of all.