[Brake conversion from i to GT.]

I'd like to convert the brakes on my '05 Legacy i to the GT brakes because of the added stopping power and I do a lot of driving on Washington back roads, up and down mountains. Any suggestions, or if I'd be spinning my wheels so to speak please fill me in. Thanks.

[O2 Sensors in Legacy]

Are universal O2 sensors ok to use? I'm not worried about the extra wiring work involved when using a Bosch universal O2 sensor, I just wanna know that it's not gonna cause problems with the pcm or fuel trim system.