I'm a bit late to the conversation but I'll throw in my 2 pence. I'm curious as to what qualifies "OEM is the best" like a few people have said. Is that performance-based? Initial bite? Fade resistance? Pad life? Dust? Noise? What makes a pad better than any others? I'm new to trucks but have a decent amount of experience with cars, so bear with me.
I had a Subaru STi that had Brembo brakes from the factory. The stock pads were okay, but they dusted like crazy. I swapped out the pads for some Hawk HPS. The Hawks had a better initial bite and lower dust. I also changed out the Brembo blank rotors for Stoptech slotted rotors. They were much better in the rain than the blanks and very similar in dry conditions (slotted do have a little less surface area due to the slots so some people say they sacrifice dry braking performance for better wet performance. I didn't notice a real difference in dry, but I changed the rotors at the same time as the pads so those may have affected things). I also changed out the original rubber lines for Stoptech stainless lines and the original fluid for Motul 600. Overall, the brakes were fantastic.
My Aston has Brembos from the factory as well, but with slotted rotors and stainless lines as standard (as opposed to blanks and rubber, respectively, on the STi). The pads were changed out for Pagid or Porterfield (can't remember which), and I have brake cooling ducts (but I'm not sure how effective they are due to routing). I track the car and never have any braking issues, usually doing 4x 20-minute sessions per day for 1-2 days.
I'm looking at upgrading the brakes on my T4R and haven't decided which way to go yet. I'd like to get slotted rotors for my T4R but I'm worried about getting small rocks stuck in them. This DOES happen with my Aston, and it's a road-only car. I'm worried that an off-road vehicle will be far more prone to it. (Quick note: rocks getting stuck is generally only a nuisance and is easy to remedy, doesn't cause any problems but you can hear and feel the rock.)
I always steer clear of drilled brake rotors. They're very prone to getting debris stuck in the holes, and they aren't as structurally sound as blanks or even slotted. The big exception to this are exceptionally expensive. I definitely wouldn't trust cheaper rotors, like those that are offered for 4Runners.
There's really no downside to upgrading the lines and fluid except for the cost of them, so I'll probably be doing those when the time comes.
Of course, take all of this with a grain of salt. I'm not an engineer. But I did stay at a Holiday Inn Express last night.
