In defense of Sibelius (I must use it for School), it is unbelievably
fast once you master all the hotkeys and get used to that insane ribbon menu system introduced in 7. In addition, the sound packs are phenomenal, the amount of plug ins are staggering, and you can tweak the playback in literally anyway imaginable, as well as the engraving itself.
If you are only engraving notation or need to hear something play back quick and dirty, Musescore is a great choice. However... If you need a Formula 1 car opposed to a Sedan you want Sibelius.
Sibelius is really for the power-user, containing many features not used by anyone except professionals or students. Heck there is even an option to check for parallel 5ths!
It's Photoshop vs. GIMP.
P.S There is guitar fingering in Sibelius, for both strings, left and right hand, as well as tab, chord diagrams, etc. Lute tab, medieval notation, are all supportable via the plug in system (I am 90% sure about this)
Armed with Book, Forum, and Guitar, I will bare my teeth and face the world! Music is a way of thinking, an art. There is nothing more demanding, and nothing more rewarding.
Alvarez-Yari CYM-75 Masterwork