I hated the original FOLLIES, but then I listened to the concert version and i just LOVED it. It is just so incredible. FOLLIES originally didn't grow on me, i liked probably two songs, then I listened to the concert and i loved practically all of them, I still don't like "Live, Laugh, Love". Which brings me to my point. Really you have to have a good or great performance in order for a Sondheim show to work.
You need the following: great dictation, great stage presence, carrying a tune isn't a huge requirement but it does make the song nicer.
My least favorite, please don't hate me for this, is SWEENY. I do like "Not while I'm Around" and "Worst Pies in London" not to mention "A Little Priest" But everything else to me isn't so good.
"Sing the words, Patti!!!!" Stephen Sondheim to Patti LuPone.