The Ruger is an extremely strong and reliable revolver. I have big bore handguns from a few different makers, and almost always end up shooting a .44 or .45 single action. I almost never shoot my S&W 629 double action. I normally carry a Blackhawk in the field.
The Blackhawk is so simple and rugged that it is a safe bet that a used gun will be in the same condition as a new gun, except for holster wear. I would buy the Blackhawk.