Given the choice of these movements commonly used in the replica divers:
1. A2824 (or ETA)
2. A2836 (or ETA)
3. Powermatic 80
4. Miyota 9015
5. Clone 3120
I will pick the 2836 all day long especially on a closed caseback model, for the ease of maintenance and instant date change. The Powermatic80 movement can be serviced don't get me wrong, but parts may not be as readily available or regulation may not be as simple even if it is a modified ETA movement.
Remember though, this is my preference. It is not an absolute choice for everyone.