Also, I think this is a single piston caliper, and the caliper has to float to compensate for brake pad where. If this is gummed up or rusted, it will tend to cause the brake to drag and wear unevenly.
I know you put new pads in recently, the first two causes mentioned will cause even brake pad wear, and my comment, causes uneven wear. Do you remember what they looked like? Call me at home before 6 pm if you want to discuss! I'll be away until Tuesday after that.