Vorpal does not look how it is meant to look at this rank. It is supposed to be very consistent but the appearances go on then off rapidly. Rank 9 looked like a upgrade compared to rank 10. In the character window the enchant looks how it should, but ingame it looks very spazzy and glitchy. Nothing like how it's supposed to. When you use an encounter power or an at-will on your mount the visual of vorpal rank 10 will disappear and the only way to get it back is to disable, and then re-enable it.
1) put a rank 10 vorpal enchantment in your weapon slot and make sure the visual is enabled
2) get on the mount and go to a pack of enemies
3) stay on the mount, but use an at will or an encounter power
observed result: the visual of vorpal disappears even though it was enabled
expected result: for vorpal to be seen as it should when getting off the mount