I would say none, since Colt revolvers like the Python, Peacemaker, etc. are inflated due to high demand and the "Colt" name itself. Even King Cobras,aka the "poor man's Python" which you could hardly give away 10 years ago are now going above $1,000 on GunBroker. $1,000 will still buy you a very nice Registered Magnum if you look around.
If I had to choose one that would be the "equivalent" to the Python as far as demand and value in the future, I'll agree with the above, the Registered Magnums and the Model 27's with desireable features, like the highly sought after 3.5" models.