AUTOTUNE_LEVEL vs roll rate, looking for advice on tuning for max performance

The docs for AUTOTUNE_LEVEL say “Levels above 8 should only be used by very experienced pilots.” But even level 11 is only 300 degrees/sec.

For a medium-sized reasonably-acrobatic plane (1m wingspan) it’s pretty easy to roll 360 degrees/sec. Is there a risk of instability if I try and tune ArduPlane to try and get close to the roll/pitch rates achievable in MANUAL mode?

If I autotune with AUTOTUNE_LEVEL at 6, should I autotune again with it set to 11 and then do some manual tuning as per Roll, Pitch and Yaw Controller Tuning — Plane documentation, or should I just jump straight to the manual tuning?