I took apart my front brakes to find which parts I'll need to replace in addition to the pads.
The pads are genuine Honda parts, they are having 45,000 miles



The rotors are original 83,000 miles (note wavy surface)



The brake pedal has random vibration during light application on speeds above 50 mph

The pads are having light taper, however the caliper guide pins are not sticking



There is a gap between the pads indicating that rotor surfaces are not parallel to each other. This probably causes pads to dance on the rotors during initial application



an "expert A " told me to stop abusing brakes; an "expert B" told me to invest in drilled and cut Brembo rotors with ceramic pads

So which expert is right?

 

Expert B is not addressing the cause of the issue.

Expert A might explain what kind of "abuse" would cause this.

 

I can speculate that:
-the pad material heats up more as the pads are getting thinner and is more coarse grained close to backing plate. (you can see "rivets" on the linings)
-(this is an absolute guess) the rotor has a very thin wear resistant layer near its surface, once it wears out, the rotor wear is getting out of hand
I'll be buying new pads and rotors and, of course, the genuine parts. So if my car will be totaled someone would be lucky to get them for a fraction of the cost!

 

We still have Factory rotors on our '07 (145K miles in salt-laden NJ). They are just starting to cause a slight vibration, the Rusty Ridge on the edges is severe. (But, I adjust the rear shoes every year, ~15K miles.) Our fronts are lasting ~60K miles each set.



You are correct about thinner pads not dissipating heat as well as thick, new pads. (That is why organizers recommend changing pads before an HPDE/track day if they are more than 1/2 worn).

 

Now that you have done this perhaps you will bless me with unrelated answer:
Where would a marble-sized pebble lodge that would cause an ungodly loose rattle
at low speeds for 10K+ miles where it could not also eject itself?

I just had one "removed" for a fee. After years of living on gravel this is the first
car to have such a noise...other "in brake rock noises" (in other vehicles) were always
curable by going in reverse and hitting the brakes. I am suspicious the sound wasn't some
easily solved heat shield clatter yet I got a bill for a complete brake disassembly.

I must admit it seemed to coming from there but I've never run into a brake housing
that could take and not give back on its own (especially for something loose).

 

I'm guessing it made its way between the rotor and backing plate and stuck behind backing plate to steering knuckle mounting screw. had same issue on my other car (87 Camry)
BTW I did some research and found that when the pads got thinner that 1/3 of its new thickness the heat generated with my braking created "hot bands" on the rotors



which are also responsible for brake pedal vibration under certain conditions
"this rotor caused vibration when the brakes got hot.."
source: rotors hot spots and brake pads - Auto Maintenance Discussions at Automotive.com
How come my 79 Supra with solid non-vented rotor, primitive caliper slide (no lubricated pins just plane stainless shim with spacer) and stamped steel caliper bracket was able to stop the car without brake pedal vibration at the shorter distance than Fit ??

 

guess I'll go real slow on gravel and change my pads early...