Funnily enough, they all taste pretty much the same to me.
Johnnie Walker Princes Street and McConnells in Belfast are worth a visit though, purely from an experiential point of view.
You've not been properly introduced to whiskey by someone familiar with it but you have to have to patience and some expendable income. This all sounds snobbish but it's the God's honest truth. Too many people just do shots of whiskey and base their experience off that but that's like learning the nuances of using a slingshot by practicing with a trebuchet; all you're doing is singling yourself out as a newb and ruining your experience with blunt force trauma to the mouth.