The Griffins are decent bindings but most would agree the Tyrolia Attack 13 is a nicer binding with lower stack height, better retention and they are easier to get in and out of. Best of all you can get last years model of them for $129.99 from places like ASOgear.com in the 95mm brake(actually 97mm) width which is perfect for that ski.
The only ARV that could be mounted center without fighting sidecuts/tip tail tapers would be the more symmetrical ARV86. The ARV 96 and 106 need to be set back at least 2cm or more back from center due to their more directional sidecuts and larger tip/tail taper. They won't be as stable for carving out of the park more forward than that.
For your use, you should be in the 2 to 2.5cm back from center range on the ARV 96. All-mountain mark is in the 5cm back on those skis and 2.5cm back is the 50/50 all mountain/park mounting line as recommended by Armada who makes/designs the ski. It's 6cm back , 3.5 cm back for those settings on the ARV106.
Quote from Roofbox review from this site on the ARV 106 who normally rides center mounted skis in the park.
"For reference, I mounted my own pair significantly further forward than recommended which is at -6.5 (with a secondary recommended point at -3.5). Iíve tried a few different mounts and concluded -2cm is my favourite. I probably wouldnít go all the way to true centre myself, because of the sidecut setback but at -2cm they they still carve well. If youíre used to a centre mounted non-symmetrical park ski, the feeling of the ski at -2 is comfortingly familiar. Further forward than that and you do start to notice you are fighting the sidecut, further back and you lose the sense of balanced weight which I can't live without in the air."