Curious.
With other things being pretty much equal, the 'problem' area is the right border, but the PSA 9 OC has a bit more room there than the straight 8 does...
...and I won't even mention how significantly wider the left side white area is on the 8.
From PSA:
MINT 9
Centering must be approximately 60/40 to 65/35 or better on the front and 90/10 or better on the reverse.
NM-MT 8
Centering must be approximately 65/35 to 70/30 or better on the front and 90/10 or better on the reverse.