Interesting your mentioning this gun had an undisclosed loose rib. I purchased an A Grade Three Barrel Gun Co side x side from Cherry's; and when received it also featured a loose barrel rib in spite of the fact that the seller had the gun in hand as I asked detailed questions to include barrel condition. The loose rib in the above pic, although fairly obvious is not glaring; this A Grade gun featured a big glob of solder along the last two inches of the rib near the muzzle that a blind man would notice. When questioned the seller said he'd simply "overlooked" this issue and offered a refund; no discount. The gun was in overall good condition otherwise so I elected to keep the gun because examples are so rare (when have you seen one marked TBG Co?), but I no longer completely trust Cherry's for an honest assessment. Now to be honest myself, I later purchased an O Grade TBG Co drilling 12x12x32-40 from Cherry's that I was advised had issues and didn't function at all, and did so as the parts alone were worth more than I'd paid. When received and examined I found the right side cocking rod/hammer unit broken and the cocking "ear" broken off the left side of the cocking roll in the barrel lug. Figured it as a wall hanger for sure; then wonder of wonders, the very next week see on eBay a listing that included all internal parts for a Hollenbeck (these were Royal Gun Co parts) action to include a barrel lug complete with cocking roll. Someone had done something to blow up this barrel set and had blown the lug completely off in the process. I won the auction for $50 and Buck Hamlin worked his magic to put this TBG Co. gun back in service.
