Is the drop rate rolled per item dropped however? Or do mounts exist on a separate loot able?
For instance:
Epic A = 1%
Epic B = 1%
Epic C = 1%
etc
OR
Epic A = X Chance at Non-Mount Item
Mount = 1%
If it is the first option than yes Heroic 25 would have a higher loot chance of mount (if it can be dropped). I can confirm from a Game Master that Handmaiden drops only 25H and Blazing drop only in Normal Mode.
Lich King must be done on Heroic 25
Ulduar can be done on any 0-Lights
I will look into Experiment on Normal