How to know what to buy?

We will be in Edinburgh for a few days then a week throughout Scotland ending in Glasgow.. Would like to taste some Whisky at a bar or store before we buy. Used to like Peaty/smokey in the old days but have since become a bourbon drinker. From what I know, which is very little, believe that Speyside or Lowlands might be more my taste. If I try a few while in Edinburgh can I generalize enough to buy the same region that I like or do I need to taste the exact same item that I plan to purchase? Understand that Cadenhead is the best source for Whisky but doubt I can taste the same bottle that I’ll be buying. Or..should I wait to buy to bring home some Scotch until I’m in Glasgow? Hope this makes sense- please be kind.😀