Get a Saiga. You can modify it to be a really really good Self Defense shotgun.
As for the Remingtons, they will work, but if you go up to a 12ga, you will find more accessories if you want to make it more tactical and less like a hunting gun that does double duty. Remington also makes off the shelf self defense shotguns if you go to a 12ga.
If you want light, and wont be tactical-izing it, then I would actually look at the Franchi AL48. Super light, and runs on the long recoil system like the Browning A5 of old. I have the 12ga version and love it. It is my go to field gun because its so light and never hangs up. No gas system to clog.