The modern made Walker replica has corrected the original Walkers primary problem by virtue of the steel it's made from.
The original Walker cylinders were by today's standard little more than wrought iron, and couldn't take the 60 grain powder charge, and many blew up in the field.
Additionally, it was overly heavy at almost 5 pounds, long and cumbersome, and had a wimpy loading lever latch, which falls down, locking the cylinder under recoil. The earlier Patterson used the same latch, but was 28., 32 or 36 caliber at the largest with insufficient recoil to drop the lever. (That is on the Pattersons that even HAD levers to begin with).
The 1848 and later Dragoons had a shorter barrel, shorter barrel lug, shorter cylinder with a loading lever latch at the front instead of the rear. The maximum charge was 50 gr of powder, and even some of them may have blown up as well.
They were still, at 4-1/2 pounds, Horse pistols and were carried more often on the horse's saddle in pommel holsters rather than on the soldier's hip.
The 1860 Army, 12 years later, had significantly better steel in the cylinder and barrel and allowed its much smaller and lighter frame.
The Walker is a hoot to shoot with tremendous flame, boom and smoke, but be aware that a diet of 60 grain loads will loosen up even the repro and crush the wedge in time. Most shooters load the gun to 40 or less grains of powder, and fully load it only occasionally for show and thrills.
The conversion cylinder for the Walker requires the barrel to be removed for loading and unloading, so is a bit slow and inconvenient, but is very accurate and a fun thing to play with. The 45 Colt cowboy loading will not hurt the repro Walker.