Unicode accidentals vs. Markup accidentals

[Saul Tobin]

Surprisingly, typing the Unicode characters for accidental symbols does not
produce the same font output as using the markup commands:

<<
  \new Staff {
    c'1^"B♭"
    c'1^"C♯"
    c'1^"D♮"
  }
  \new Staff {
    c'1^\markup { B \flat }
    c'1^\markup { C \sharp }
    c'1^\markup { D \natural }
  }
>>

And neither looks particularly great IMO.