The older trap barrels with the raised rib were considered better quality and I believe they were better made and had wonderful chokes. The Hasting trap barrel offered from Shooting Sports magizene is of very high quality with a hi rib a bit pricy new but look for a used one if advailable. Look any used barrel over closely for bulges straightness rib condition and most important in 1100 barrels is the condition of the lock up area inside the back enf od the barrel where the bolt locks into the barrel. This is where the wear occurs if should be deep and sharp in the recess not hammered or rounded or worn away. I should add that this area can be fixed welded up and recut and start a new life price is the issue and time and trouble involved. I would prefer a good used barrel and avoid the hassel myself but if I could save a old trap barrel with a raised rib for a great price I'm a sucker for projects like that.
Happy New Year and good luck,
Buddy