I've got the 1894 Marlin in .357/.38. It's the Cowboy with the octagon 24" barrel. I've shot it in CAS for four years now and have many thousands of rounds through it. I love the gun. Reliable as a brick, and accurate.
You are right, in that Marlin has ceased production of this gun in the 24" barrel. They produce it now only with a 20" barrel. I like the slightly longer barrel, so I guess I oughta be looking for a backup gun, just in case!