Greetings, Pohill
Buy the Ruger! They are a joy to shoot, they are made of better steel, and fit and finish are much better. They also have modern lockworks, with coil springs that DON'T BREAK!!! If there is a shop nearby, where you can see the two side by side, I don't think it will be a much of a contest.
The Ruger is also very strong, as it is based on the Blackhawk/Super Blackhawk. If you get a conversion cylinder, the Ruger will handle any .45 Colt ammo you care to use, unlike the Italian guns, or any Colt SAA. I've read where they were tested with Buffalo Bore ammo (1450 fps), and the gun did just fine. You can get a cylinder from R&D, but it will be nickel plated steel, not stainless. Bigiron can make you one out of stainless, and their prices aren't bad at all.
The Ruger is more expensive, but well worth it. You can get a good deal on a new one from most of the dealers who are selling them on Gunsamerica.com. They have used ones also.