There are a couple of key things you need to be aware of in regards to the virtual tilt back and FRFR in general.
1st thing is, Virtual Tilt back is only turned on via one of the backline modes (Guitar, Keyboard, Acoustic) while the speaker is in an upright position and is not mounted on a pole or turned on it's side.
Virtual Tilt-back optimizes the speaker tuning to achieve an upward tilt to its main axis and the idea is that it helps aim the sound upward towards you when the speaker is placed on the ground (like and angled 4x12 cab).
HOWEVER.....when you use "Electric Guitar" mode while you will get the virtual tiltback feature actived, you won't be playing FRFR as the Electric Guitar mode turns of the tweeter and just uses the subs (again, just like a 4x12).
I can say with experience (and in my opinion) that using P.A. mode to get FRFR with a Pod HD using L6 Link gives you the best sound anyway.....the Electric Guitar mode might be better if you are plugging direct into an input with another external Amp Sim or whatever, but Electric Guitar Mode really lacks definition with the HD units.