Well, I don't know GuitarPro really, but once I tried to print a score without TAB and could not
produce it - that was the critical reason not to use it. And I don't know how well GuitarPro handles scores for other instruments
(like piano or flute) which are no problem for Finale.
I've been working with Finale (version 2012) since almost two years now - it is a universal and mighty product,
but you do need a good manual to get started. The only thing I couldn't do with it was to typeset lute scores in French tablature,
but there are other tools for that purpose (Django, Fronimo).
Like Finale, Lilypond + Fronimo make a universal tool, but the input language of Lilypond needs learning and experience
and may deter those who are looking for quick results. As a retired computer scientist I am used to formal languages,
have used TEX, with its descendant MusTEX a predecessor of Lilypond, and so my opinion is biased.
But your question is a good one - a book might be written to try an answer.