Well personally I bought several of them and put them on normal mounts and it seems pretty similar to me, will probably buy a few more for slower mounts though since it's actually somewhat worth it then.
On the grand scale of things I don't really see the point in needing extra mount speed when we have the ability to eat five bushes and zoom across the gmap lighting fast and now with the addition of warping which just makes it even more fast.
Should nerf bush speed or remove it altogether.