I just replaced the front and rear brakes on my TL at 90,000. The fronts were no more than halfway worn, probably less. It should've easily gone another 90,000. The rears looked like new still. Only reason I touched them was to install the 13" aftermarket brakes.
Brake replacement is super easy. It's a matter of removing two bolts, pushing the piston back in, and reversing the procedure.
If you swap out rotors, do yourself a favor and don't even try to get the aluminum assembly line retaining screws out with a screwdriver. Either use a screwdriver that is made to be hit with a hammer or drill them out. Drilling them with a 7/16 drillbit literally took 5 seconds each. I recommend doing it this way.