Pros:

- Slow motion
- Looks awesome with melee weapons (especially ones that can decapitate zombies).
- A great mod to catch those zombies by surprise.

Cons:

- None really, except my pc kept crashing before I moved most mods out of the addon folder. Maybe it's just me.
- Makes gameplay easier XD

Conclusion:

It's a great mod and I had a great time derping around :D