The thing is I have no idea how the pieces work.
If it's one slot, applies to all mounts, then in order to have the water walking at all, I have to give up the other powerful perks like no dazing.
I mean I still have the swimming mounts which I assume will keep their special effect but those aren't as good!
The parachute thing is a must for war mode with flying enabled, the no daze for when we don't have flying, and the water walking for zones with a lot of water. I expected to just put one on a flying mount, one on a ground mount, and one back on the strider where it was.
Especially since this will translate across characters. Water walking would be insanely useful on a gnome who keeps sinking into puddles, but totally useless on a death knight who has the ice walking.