My first choice was between a GP100 and 686; leaning toward the GP. Then, I decided to go for an older, out of production gun, looking for something special. I was about to settle on a Security Six SS when I started looking at the Colt Python
GP100 all the way.
The Ruger is an excellent gun. It is a total redesign of assembly, locking, and manufacturing. The 686 is a good gun, sturdy, accurate, etc, but is an updated 75 year old design, a good design with good metallurgy, but still an older design. The Python you mentioned is an updated 100 year old design, parts are hard to come by since it is out of production, and in general it is not a very rugged design when compared to the other two.