There's a notable problem with the rear brakes on the 4th Gens. Mine were worn out by the early 30ks, same as all my friends and family that have/had 4th gens. I use the brakes very sparingly - anticipating slow/stops, engine braking and I live in a rural area with little traffic. I believe part of the problem (if not most/all of it) is the emergency brake system - it doesn't release very well. I can't tell you the number of time that I released the pedal and it still had the light on, and took several tries to get it to go off. And my guess is that even when the sensor said it was released, it wasn't always fully.
The 5th gen has an electronic one that hopefully solves that problem.