Not at all the same! The heavier bullets from the .45 Colt will impact much higher than roundballs.
I'm working with a Kirst Konverter in an 1860 Colt repo right now. I had sights set to shoot dead center at 25 yards with the roundball over 28 grains volume of Pyrodex or 3f Goex in the percussion cylinder. With the .45 Colt I had to make a much taller front sight to get my shots on paper. I won't bother trying for an exact zero untill I settle on the exact load I want to shoot. As of now it is about zeroed for a 200 grain bullet at about 800 fps. With that zero it throws a 250 grain bullet about 6 inches higher and a roundball about six inches lower, so a total of about one food difference between the roundball and the 250 grain bullet. My guess is you also will need a taller front sight to bring the point of impact down to the point of aim. If you have the new front sight dovetailed to the barrel you can also adjust windage by knocking it side to side in its slot.
So when they say you can switch between percussion and cartridge in seconds that does not take into account actually hitting anything, because to do so will also require switching sights. Of course you can load roundballs in the .45 Colt cartridge and likely still shoot to about the same POI as with the percussion cylinder. I shot some just today with 6.2 grains of Trail Boss and got 740 fps compared to 1040 fps with 28 grains volume of pyrodex, also loaded in .45 Colt cartridges. I had never chronographed that load from the percussioon cylinder and was pretty surprised it ran so fast from the .45 Colt. That's not even a maximum load, I have loaded 35 grains volume of Pyrodex in the .45 Colt with a 255 grain bullet, now I'm curious as to how fast a casefull of Pyrodex can push a roundball.