They definitely work better for short text, primarily titles and logotypes. If you only have a few instances of, say, lowercase "a", then it's going to be fine

They definitely work better for short text, primarily titles and logotypes. If you only have a few instances of, say, lowercase "a", then it's going to be fine if you only have a few alternate glyphs. (Having said that, there's definitely a bit of craft, if not art, in choosing the right glyphs and getting the kerning right.)