Pros:
- Cause a good damage even without using skills.
- Hextec helps you with gaining Life Points by using other skills from shaco (like his ult)
- Guardian Angel can help you even at the middle of a teamfight
- Good at killing in 1x1 agains a lot of champions

Cons:

- Still fragile, doesn't have enough speed to gather a big amount of life points during a team fight or versus some champions like Malphite or other tanks/Offtanks.

This build of shaco worked very well with almost every champion I played together, here are somes that I played with and it worked well:
- Darius
- Teemo
- Singed
- Volibear
- Nidalee
- Gangplank

Expect for some unwanting kills steals from you, it happens sometimes with everyone, doesn't it?
Try to use a lot of your E skill to slow enemies down for your partner. Use a lot of W skills in bushes to work as wards. Use Q to help your partner advancing the lane or killing a champion, or to kill a champion yourself. A useful trick is hiding yoursel in the bushe, ulting and commanding the ult to go into the fight for you. If the enemy starts attacking the clone, use your Q skill on him, and the E skill right after it.

I'm Delacrouix and this is my first guide. I'm sorry if I missed something. I will try to add more things in the future.