The factory brembos are Extremely capable brakes, while at the same time not being super heavy either. The biggest "upgrades" you can do to them is a proper pad and rotors that can handle the heat (NOT drilled/slotted)
Terry Fair from Vorshlag ran their 2011 5.0 (full interior, huge tires, aero and 10k in suspension) with factory brembo brakes with hawk racing pads, centric rotors, and 4" brake ducting and he was doing full out braking from 155mph, and with the ducting the calipers were staying under 500 degrees. They were running 18" wheels, so im pretty sure any wheel youd wanna run would clear brembos fine, as long as they were 18x9 or larger with the proper offset. But their car holds like 15 lap records across the country in the class(es) they ran.
Your best bet for rotors are OEM quality cast iron blanks, like centric or reybestos, Check Rockauto or Tasca for cheap prices on those. Then hit up jayman for good pads.
IMO, the factory brembos are pretty beastly, but they need a more aggressive biting pad and brake ducting if you are going to be really using them, as well as a better quality, higher boil temp fluid and stainless/braided lines.
Ive gotten on my brakes hard from 140mph and only noticed a tiny bit of fade toward then end of the, thats with stock pads and rotors. With ducting and premium pads/fluid i suspect the fade will be gone.
But if you are looking used, and you find one with everything but the brakes, you can always do stoptech or used. But the factory brembos are a really good setup.