Sid was faster and a far better skater. Ovi was just big and incredibly agile for his size, he was so extremely good at lining opponents up for big hits.
Ovi is just pure spectacle on ice and it's amazing to watch because you never know exactly what's going to happen with him with or without the puck, either way he's electrifying.
Sid plays a pretty straightforward grinder game with extremely high level skill and that in and of itself is spectacular, the fact that he does it so fast and has generated the results he's generated is what is truly remarkable IMO.