4-3-3 is a very strong offensive formation. I played against it yesterday in the cup using 4-1-3n-2. All his players were 6 stars but somehow I beat him 5-1 on aggregate. 1-1 the first round and 4-0 the second time. If you played 4-1-3w-2 then he probably focus passing through the middle which could really give him/her the advantage. To me every formation can be beaten!