So far, all of the versions of Stronger With You smell very similar, so having more than one seems redundant to me. Having said that, the Leather version is my favorite because it has a subtle, dry leather-oud note that mixes with the warm, sweetness of the nutty vanilla that you'll smell in all versions. It's more balanced and refined that way, a needed improvement from the others. It reminds me of something you'd get from Parfums de Marly.
Very good performance with plenty of noticeable projection and all-day longevity.