Well, I installed my $10 tilt lever on the back of my standard RC transmitter (this after unwittingly installing the 1.0.0.6 update earlier this week). After calibrating it and selecting the Upgraded RC option, I found its actually going to be usable with the 1.0.0.6 Zen update - it has a much smoother action than the Vision app tilt control and its not to hard to find the center that holds the position of the camera tilt steady. I did find that with the Vision app tilt control turn ON, it still does do gross movements of the camera1(by tilting my Iphone) and at the same time, the tilt lever still works for fine movement. The position of the camera on the right bar is accurate when you enable the i-phone tilt feature so I know how close the camera is to horizontal or vertical.
It would still be nice to be able to choose absolute vs relative tilt but I think this will still work better than just the phone tilt feature alone.
Maybe the next update will do that fix.