A shotgun is an excellent choice in a home defense weapon.....
But not with a pistol grip. They're just not practical. They sell a lot of them because kids think they're, "Tacticool", and they're used in TV and in video games and such. They basically take a good weapon and screw it up to the point of making it useless. Some years back a guy showed up at the Trap range with one when I was shooting there. He went 0-25 with it. As I said, useless.
Just to give you an idea, these are a few home defense shotguns I keep around. The top 2 are a Mossberg 590 A-1 Mil-Spec, and Mossberg 500. The 590 A-1 is built a bit more stoutly with a heavy wall barrel, and a metal safety selector switch and trigger guard that are plastic on the 500 Model. It also has a bayonet lug to accommodate a M-9 bayonet, if you're into that sort of thing.
The bottom 2 are Rock Island Armory M-5's. One in satin Nickel, and the other in a Parkerized finish. These guns are a very good choice for someone who is on a limited budget. They can be had for a street price under $200.00, (Parkerized Model), at some of the big box stores like Big 5, ****'s, and Academy Sports.
They are built on a all steel receiver, and are based on the old High Standard Flight King design. It has been well proven over many decades under that name. And also clones built for Western Auto, (Revelation), Sears, (J.C. Higgins), and Wards, (Western Field) over the years. All are the same proven design as the Rock Island Armory M-5. Any or all of these guns would serve you well in a home defense role, and will outlive you. All the guns shown are in 12 Ga. with 3" chambers.