Just do Si rear discs and you'll be good. Front and rear discs, good rotors and pads will stop better, along with bleeding the lines and replacing the brake fluid will help with stopping.
Personally I like Brembo Blanks and Hawk HPs or EBC Greens.
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Mazda 2 Forums
R.I.P. Pablo 'Fathead' Garcia - Love you man! See you on the other side!
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