Ok i just did some searching around and I am curious, because the term cat back would refer to from the catalytic converter back correct? Well then does the aftermarket "cat Back" exhausts include the Y pipe? My Y pipe has a small leak in it and i am wondering if I buy any of the "cat back exhausts" they will include that part or do I have to purchase it seperately?

The only system that includes the Y pipe is the Nissan Sport exhaust. None of the other aftermarket systems come with it sadly. Probably wouldn't cost a lot to have an exhaust shop fix you up.

I recall reading that some of the cat-back products aren't as good as others. Any feed back on cat-backs? (I could be affected by the good old english porter I'm drinking.....)

Your better off having the Y-pipe replaced by a muffler shop. As far a a catback system, I have a Borla stainless system on my 04 X 5sp. Nice mellow sound, not too loud, but a nice growl. The system cost me 408.00 direct from Borla. Garenteed for 1mil miles.