I prefer it to be realistic. Zombies are slow and shambling because moving tears muscle fibers, and as a dead body, those don't heal themselves. They can only move fast a couple times before falling apart. Which, for a virus/bacteria/mushroom/parasite zombie plague, would make sense for a lunge to reproduce by infecting another host.

So in other words, I like the super slow shambling zombies, that can, once or twice, move very fast, but then fall to pieces, no long chases, you dodge and you're good from that one forever after.