Which internet connection you have is not the issue, its the ps3 network... Google this topic... There are many many articles on it...
Kdr is not everything...
(Btw my kdr is 4.51)
As with all my friends, and many many people online, I have played both ps3 and 360 online on the same 22.5d/5.5u connection. There is no comparison (fairness wise).
Like i said, ps3 is great for casual gamers who like to have fun and do not mind unbalanced fights. (Even when its in your favor).