If you want to shoot rimfire cartridges and lower pressure cartridges like 30/30, get the Contender. If you want to shoot high pressure cartriges like 30/06, 300 Win. Mag., etc., then get the Encore.
The minimum length for a rifle barrel without special paperwork is 16 inches. The barrels are easily interchangeable without modification.
I can't think of too many cons. There is a recurring question of the legality of converting what was set up as an Encore or Contender rifle to a handgun configuration. For peace of mind, I would advise you to decide whether you want a rifle or a handgun. If you want a handgun, make sure the frame was originally and ever since the sale used only as a handgun. If you want a rifle, it doesn't matter what the original or subsequent configuration of the frame was.
Ah! Another con; it's hard to have just one or even just two barrels.