I prefer street fighter overall. Especially thanks to the Alpha trilogy. Alpha 3 was and still is the fighting game I always come back to. Oozing style, great pixel work, music and the fighting system was the perfect balance of classic street fighter but also fast / explosive. Ariel recovery, ground recovery, alpha counters, different "isms", combo system which isn't heavy on the memorising input chains... However, if counting Garou Mark of the Wolves as a part of the KOF games (which I do), then I'd say at their peaks, they're close to equal. Mark of the wolves, with its tiny roster, manages to be as good as any fighting game I've ever played and I doubt the reboot will be better, but let's see.