Sound — 6
I have the Seymour Duncan Jb SH-4 in my Schecter classic paired with a Jazz SH-2 in the neck position. I wouldn't really consider this pickup as high output as it's made out to be. It's definitely no weak pickup, but it is by no means a screamer. The tone is above average, nothing special, but definitely nicer than most stock pups. When parallel it has a good sound for rock and lighter thrash, but that's about it. When split I found it has a good sound for blues. The mids are where this pickup does its best (in my opinion and in my specific guitar at least). To my disappointment, it's been a bit muddy when playing the Low E and A strings, especially in any drop tunings (Drop D and D flat for me). The definition in general is a lacking and it doesn't have that punch that I've experienced even with my shitty stock Ibanez active pickups I have in my RGA. This is surprising to me since my Schecter has a good amount of walnut and maple in the body, which should give it more snap. The highs are fair, not too bad, but not that great. Sustain is ok, but notes lose their definition quickly. I checked the wiring and soldering in the back and there were no issues there (no surprise from Schecter). Maybe mine is just old and worn out, but it's very unimpressive.
Overall Impression — 6
Overall, I don't like this pickup. I'm replacing it with a DiMarzio X2N or crunch lab within the next few weeks and all will be right in the world. If you play rhythm on the lighter side of metal, rock, and blues this should suit you fairly well. If you play lead and like a crispness to your sound, this isn't for you. I like my bridge pickup to really cut through with its sound, and the JB just doesn't do it for me.
Reliability & Durability — 7
I have no clue how I would rate the reliability on it since I haven't been able to compare my seven or eight year old one to a newer one. But if they sound the same, then the JB must hold up well for what it is.