The -8 has quite a good aerobatics envelope compared to the -4 with about 200kg typical load - two people plus a reasonable amount of fuel.
Surely, if you are allowed loops, rolls, stall turns and spins, then everything else is essentially a combination of those maneuvers.
Van's aren't very keen on flick maneuvres though they don't explicitly bar them.
There's a video of flicking a -4 on
http://www.rv-4.de/video/G-Rolle.wmv
The -6 and -7 should be getting their aeros approval before too long.
Limits are as in the PFA document; expect a roll rate of about 150 degs/s.
Interestingly, the -4 is approved for 3 turn spins, but the -8 only 2.