In addition to the leather, the TUs have the cleat sole and it looks like they have more accessories. I don't use the form keepers or the shoe horn, but the other stuff is pretty nice. Bag, shoe covers, and I guess if I have to use the cleat sole at some point, the cleat pick is nice too. The value of those things is up to you. If you've got shoe covers, that the TUs come with them is moot.
I have the black/silver TUs and they're very nice. I paid Buddies' price for the Cabrettas for my TUs, too, so it wasn't any more expensive.
SH