Seldom Seen touched on the real root cause-the rears are likely not doing their share of the braking-causing the fronts to overwork.
Lots of threads on t4r.org or YotaTech regarding the Tundra conversion. If you don't tow or ride the brakes excessively descending mountain passes, most folks never need that much of an upgrade.
Having come from a Gen 2 4Runner-the 3rd gen brakes are plenty adequate
Slotted/cross drilled rotors have their fans while others say it is a waste of money.
Save your friend's money and consider Brembo or AutoZone rotors-Brembo's maybe $20 more for the name brand. Auto Zone replaceable under warranty and some folks just swap them out every year or so.
I had Irbis do my brakes, I would never trust myself with a system so critical to my passengers' safety. I guess I must be a 1 banana mechanic.
I used Brembo rotors and the 4Runner upgrade pad-the bite of the pedal is now significantly improved. Ask for the upgrade pad-not the stock pad replacement. I can provide part number if needed.