Both beautiful specimens, and I’m partial to the 586 as I think S&W makes the best wheel guns, however, Colt has the finest mirror finish on their revolvers (at least used to, haven’t seen a new one in person). So from a beauty standpoint, Colt hands down.
I'm a Smith guy and I love the way most of them feel in my hand (except the air weights....don't like them). That said, I do really like the Colt high polish blue and the look of the vent rib. Not enough, however to pay 3 to 4 times the price to get an older Python over a S&W 586 or 686