I broke down, done gone and bought cube 6.5 a few months back... dongle shmongle, I say... I just need an integrated DAW. Plus, I justified the steinberg key by getting a really good deal on Arturia's synths at the time anyway... :) I've been using MakeMusic's PrintMusic for years for basic lead sheet stuff that I do from scratch (really nice app for the $$$, BTW). I have no real use for full-blown Finale or Sibelius, etc., in that I'm not doing full scores for film and print, etc... but I do need full-featured staff in the way that I need comprehensive MIDI, a decent step sequencer, audio stretch, etc. etc. all in one package. Rewire and XML import/export and all that other jazz is really something I don't have the patience for... which is another reason I wouldn't use Finale/Sibelius anyway, because on the DAW side they're lacking, comparatively.
I've played piano for years, and honestly, programming chords and harmonies in PRV is paaaaiiinfullllll... I don't know what it is... no, I do know what it is... I don't play piano at a 90 degree angle. If the piano keys were along the top, then I could at least see the notes naturally as they relate to the, you know, piano... but then you lose the ability to naturally "read" the notes left to right. I'm sorry, but PRV sucks for part programming from scratch. I've done it for years (in SONAR and elsewhere) and every time it takes longer to do simple things. Tweaking a live performance, perfectly adequate, but notes from scratch, very difficult, IMO. So... if I need to write in a horn section or some strings, I just need the tool that is the most efficient for that sort of job, which for me is notation. Other times I may just play those same parts in and tweak in PRV... but I need the options. I've actually programmed entire scratch tracks using only the mouse in Sonar, FL, reaper, etc., including piano, drums, bass, melody... so for me, the more tools, the better!