Wow - What a nice selection for 'pops'! I'm sure he will be pleased. If you add water, try just a few drops with just small pouring of scotch. That way if it's not to your liking, then you didn't have much anyway. And, be sure to use just a few drops of bottled spring water. Add a couple of drops, taste, then continue to add to see how the flavors open up. BTW - do not use tap water - nothing like adding chlorine to a fine scotch that took years in the making. And for you - which to start with? I'd start with the Glenfiddich, then the Macallan and then the Duncan Taylor 38.