Pros:
+Amazingly big damage after sheen.
+Pretty easy to master.
+Enemies are going to be underleveled.
+I cant list em all^^
Cons:
-If you dont succeed at early game jungling, you will be squishy.
-If you dont gank constantly, your team will fail.
-There is no more.

3v3 Jungling lets 2 people to solo and you will most likely get a first blood, so you will have 3 same level players and enemy has 2 lowers... You will be most likely getting alot of kills(assists) with this build and you will be headding to get first blood from bottom with your team. Dont start with taking red buff(or even trying to) because you will wipe to lizard at start. Start from bottom camp(which is closest to your base and clear bottom lesser camps. After youve done it, head for north lesser camps. On your way there you can approximately gank top enemy laner. Use health pot while jungling camps or ganking. Now you should have approximately 700/600 gold so you should buy Madred's razor or long sword. Next item you will get is vampiric scepter and boots. Just follow item order from now on.