I have a 12" Contender barrel and I love mine.
I would suggest going with the Contender or G2 (unless you already have an Encore frame and no Contender frame) due to the lighter weight. Advantages of the break-action gun include no barrel to cylinder gap which results in some incredible velocities and decreased noise levels. Plus, my single shot guns chambered for straight-walled revolver cartridges are more accurate in my hands than my revolvers. Also, you can cradle the gun in your hands and hold it against a tree like Gary demonstrates in this article for some very steady field shooting:
Field Shooting Positions Disadvantages include...well...its a single shot instead of a six-shot. Plus you lose the "cool" factor that comes with a revolver harvested animal!