I learned my leason with cheap pads. Got the bargain pads from AutoZone for my Expedition...9 months later they were worn out and ate into the rotor. If anyone has had to replace the rotor on an F150 or Expy you will know that the rotor has the wheel bearings as part of the entire assembly. Not cheap and not easy as the regular rotors.
I went to AutoZone and got the most expensive Performance Friction pads they had even though the saleperson kept telling me I had a lifetime warrenty on the cheap crap.
Those have lasted a while...going on two years...with little brake dust.