Hey all! Yet again I come to a question that I have no clue on... and I have not seen much on the topic of changing the braking system completely... other then just pads

... I was looking into 14" brakes for my Xfire! but here's the question... Since I want to change the entire braking system do I have to stick to only ones created for the Xfire... such as Renntech 14" ... or can I go and look into the Porsche, Brembo, and so on....
I love the brakes on my Crossfire but how sweet it would be to have extremely high power braking!
Thanks