Above unison and harmony practice with recorded fixed-pitch contraptions, record the chordal accompaniment on some keyboarded beast (or find a pianist that owes you favors) and play melodies and bass notes with the Stick'O Pain. Nothing else will get you playing in tune faster. Melodies are actually better for this as you won't find 'safe harbor' (a spot where you can cover a bunch of the tune without shifting) as often.