WP,
As far as I know, you are allowed to do them. The limitations do not preclude them, even if they aren't specifically noted; so long as you don't exceed any operating limits.
Checking the manual, Van's specifically list the following maneuvers and entry speeds for the 8 and 8a:
Loops, horizontal eights 140-190mph
Immelmans 150-190mph
Aileron/barrel rolls 120-190mph
Snap rolls 80-110 mph
Vertical rolls 180-190mph
Split S 100-110mph
And, interestingly, they make the following note:
Because the RVs have good stall characteristics and good spin resistance, they also resist easy snap roll entry. Entered at speeds below 100mph they tend to be slow and wallowing. At above 100mph high G loads are required. For this reason most RV pilots avoid snap rolls and concentrate on looping and rolling maneuvers more suited to the performance and handling characteristics of these planes.
Or, as one colleague once put it; "it flicks nicely" is a euphemism for "it has a vicious stall".
There you have it. As I see it, flick-roll them if you want, but I probably won't bother.
Damn good fun aeroplanes nonetheless.
Mk.1