Pads are probably the biggest improvement you can make from all I have read the stock calipers are more then adequate for street and limited track duty .My upgrades are based on similar set ups I have had on some of my other cars
We have our Stage 1 brake upgrade which includes everything you need to upgrade the brake system, Pads, Rotors, lines and fluid for $650. We install this kit quite a bit and it does a great job. We can include EBC's if you would like on the kit and the EBC's are also available on our site -
I installed the Hawk HP Plus pads front and rear, and had to learn a light touch on the pedal. These are definitely a big improvement to braking power. I run Solo II about 6 times a year, and these provide more than enough braking power with the stock rotors and calipers.