When I say "muddy" I don't mean 'like dirt', just...unclear. Cluttered. You get a mishmash of flavors in a blend (or a bourbon) that you don't get in a single. Singles have distinct flavors - personally, I like Islay malts that are heavily peat-smoke flavored. Bunnehabbain is one that is a little more background-smoky, as opposed to smoke-forward like Laphroaig (both of which I love). But, if you look around, you can find singles that have vanilla tones; fruit tones; cigar tones; coffee tones - it's a lot like wine or cigars, different brands have vastly different flavors (flavours?) and experiences. The nose can be completely different, too. For example, I can pour a finger of Laphroaig in a glass and 'meh' it's a glass of whisky. But if I shake a drop of cold well water off my fingertip into that very same glass? It explodes with peat smoke aroma.
If you wanna "pound a shot", go with something relatively inexpensive like a Jameson or 'bush, as I said before. If you want to experience something...talk to the guy in your local liquor store and see what they recommend.