The factory 11.75 setup is better than what MP or SSBC sells. For some reason those aftermarket guys never figured out that 11.75 rotors are better than 11 inch rotors.

If you're willing to run larger rims then you can step up to even larger brakes but the costs go up significantly. The factory 11.75 setup is adequate for most any daily driver and is very cheap to install. The last swap meet I was at there were several vendors with disk brake knuckles for sale.