I don't know about "strongest", but I think that the Colt style is easiest to tune so that it is easier on the parts and so will last longer. Keep in mind that the hammer, hand, and bolt, as well as the springs that power them, are pretty much the same between Colt and Remington. However, if you look at the cylinders, you will see something on the Colts that is not present on the Remington - the lead on the locking notch.
On a properly tuned Colt the bolt leg will slip off of the hammer cam before the cylinder is aligned with the barrel - actually the bolt releases up into the lead and is held there by spring pressure. As the cylinder completes its rotation in alignment, the bolt spring then pushes the bolt up into the notch as it aligns.
So two of the three events that occur - aligning the cylinder with the barrel by pressure of the hand, and the sear dropping into the full-cock notch - can be separately tuned to happen together just by adjusting the length of the hand, and the third event - the bolt dropping into the lead - can be adjusted independently by adjusting the length of the bolt leg, just so that it comes up into the lead. Makes it a lot easier for a gun butcher like me to get it all right.
On the Remington, with no lead into the cylinder locking notch, I think that all three events have to be tuned together.
Am I right?