Which Exhaust Manifold?

[gsxer]

I do have a 1g intake manifold and a 1g throttle body. And an o2 housing would be good for the car?
And I do have the whole cat-back and down-pipe. Do you know how much the LSE o2 housings are running for?
Are they better then the EVOIII o2 sensor?


thanks sorry for all the noob questions.

-Yinchinzhong --cheng