just a word of caution, deleting BIAB will lose all your RealTracks and RealDrums (except drum sets 1-3). You'll also lose all your midi styles and the ability to create a song from the chords in BIAB first. Fine if you record everything from scratch but as far as I can see PT will then give you nothing Reaper (which you can get for free) will do or Audacity.

PT works like RealBand as the finisher for BIAB projects.