Never had a problem with a Seymour Duncan pickup.
I've contacted them a few times with questions, and have always had my questions answered thoroughly and promptly.
Let me start by saying I dislike ceramic magnet pickups, for me they are too compressed sounding, and too harsh in the highs, I prefer the warmth and openness of an Alnico II or V. With that out of the way, I love the Seymour Duncan Custom.
The Custom is a high output ceramic pickup, with tight punchy bass, cutting highs, and a good amount of midrange. What I like about the Custom is that though the ceramic bar gives it an inherently compressed sound, it isn't overly so, to my ears ceramics typically have a nasally sound, not the Custom, it's just tight. The highs are also not brittle, they are sharp. It's sensative to pick attack, articulate, and rich with harmonics. It's not a modern sounding high output pickup, more of a hot rodded angry PAF sound.
Currently the Custom is installed in an Ibanez SZ520, which is basically a double cutaway Les Paul style guitar, thick mahogany body and set neck with a maple top, and to me sounds killer, along with the Duncan '59 in the neck position.