Quick protip if you are going from an AMS2300 to an AMS2500, or even plan to in the future:
Leave 3U of space above the AMS2300.
The reason I say that is because the AMS2500 does not have any drive bays like the AMS2300. You will need to get an empty expansion shelf and transfer all 15 drives from the AMS2300 head to the empty one. If you don’t leave the space then you’ll have some extended downtime as all the shelves get reracked up 3U.