Laphroiag 10yr or Bowmore Mariner 15yr for Islay
Glenmorangie Madeira or Glen Ord 12yr for Highland
Glenlivet 21yr or Glenfarclas 17yr for Speyside
Longrow 14yr for Islands
But honestly there's so many brilliant whiskies, each with their own individual characters, that it's impossible to pick one as my favourite or go-to dram. Just like cigars, it depends on the day and mood.... that's probably why I have 50+ bottles of scotch in my cabinet