My experience with Rossi guns is limited to my .38 spl snubbie in stainless steel. It's quite a nice gun for the money. I've shot many hundreds of normal pressure .38 spl rounds through it. It's broken in real well and has a nice reasonable double action pull and a crisp light single action pull. However, it is starting to loosen up. Therefore, if the Rossi single shot rifle is made of anything like the same steel as my revolver, I would not count on it as a survival gun. I would opt for something with better steel that wouldn't loosen up so much over time.

Wow, Art, that was a great answer. One question (might be stupid)- using either the barrel liner or the chamber adapter- Would that screw up the choke on the shotgun?

The drop in liner barrels, so long as they aren't so long the actually run into the choke, they're fine for the choke.

I've tried emailing that vendor three times in as many months. No response. I keep seeing their adds in print publications, but that kinda makes me wonder about them.

Seeing as that the slug is considerably smaller than the original barrel and choke bores, and the design keeps the liner barrel fairly well centered in this bore, the chances that your choke would be damaged would be very small.

The greatest risk to the shotguns bore and choke is that you might shoot shells with corrosive primers and fail to clean the shotgun bore frequently enough to prevent corrosion.