I've worked with several Contender barrels and one carbine. I still have the carbine - a .30-30. It shoots very well. I've had both good, and lousy barrels.
If you buy a new gun/barrel I think it will likely be good. MGM or Bullberry customs have an excellent reputation. I'd be leery of used barrels, especially older ones, unless they were known good shooters or were guaranteed.
