Has anyone played where it seemed that there was a delay between the button press and the onscreen action? I played a game that was very annoying where I'd press the button and wouldn't get an immediate result. I lost the ball on several occasions and my passes weren't quite where I wanted at times because of this as well. Also, it was part of the reason I gave up a goal as I was pressing "B" to clear it and it didn't happen and then my opponent kicked it into the goal. It was very frustrating.
In the game? No. The menus are very delayed, but the actual gameplay has been butter-smooth in my experience so far. If you're getting lag, it might be your opponent lagging or someone on their router surfing the net.
Only experience in FIFA in which I have ever had lag was against XTREME the other night, and I always seem to have lag trouble vs him (not the only one). Even when I play my friends in Europe and Australia I don't get lag.
