I just picked up a shotgun from a friend. It's labeled as a 590. I'm curious on the exact variant. It is a 7 + 1 with an extended barrel 22in. I tried googling it, and I couldn't get an accurate answer.

Working on rebuilding my shotgun collection and started by replacing my 20 inch Maverick. My question is, is it durable enough to pit more money into (Light,Shell carrier, red dot) as a HD/SHTF gun? I will also be doing another Shockwave SBS build with light, dot, etc but I'm not sure if it would be better to spend money on the Maverick or Shockwave first. I did purchase GG&G sling mounts and a fiber bead for the Maverick.