Lasted longer? More likely a gimmick to get more money from suckers. Like Many coatings for tools do not double or more the life for wear out but cost a lot more. Most helps for rust a lot but for wear very little. Worse, many "owners" at high dollar level Lease them for 3-5 years. If kept longer many do not service themselves just write a check to the dealers that rob them. So you're likely to never get a real world answer to life time.
Dusting is mostly a pad compound problem. Most Anything fighting dust means less pad worn for braking. Pads need to Wear for braking and softer then rotors. If Hard coating on rotors works then pads could be harder to wear less but may have other problems like stopping in wet weather. (Pad can hydroplane etc too. Even giant disk sets used in Amtrak et al trains can have brake issues in wet/snow weather.) If hard coating on the rotors fails then the iron base metal will quickly wear out.
"Brake pollution" is why EPA and others are limiting Copper and other things for pad/shoe compounds.
Many products now on the market and as OE from car makers are Low or 0 copper compounds.
Example: Wagner
ThermoQuiet brake pads labeled OE21 Low Copper.
Google:
low copper brake padsSide note: Wagner now list ThermoQuiet for all Fiero again but only for Pepboy at
www.wagnerbrake.com but others do have them. They stopped making/carrying them a few years back. Many PFF users love them including me.
TQ often get a rebate 1 or 2 times a year and often go on sale or cheaper at some outlets making them cheap as low grade pads available. If you think you need pads in next year watch for the rebate and get them then.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave