I haven't read many of the replies to this. But isn't it alittle biased of a question for this forum? Wouldn't it be more appropriate, on, say Ultimate Guitar?
However, since you asked, I'd say Duncan. I've yet to come across a DiMarzio pickup that I like. And while there may be Duncans that I am no fan of, there are some that I would definately consider buying. Duncans, Fenders, Gretsch and Rickenbackers make some of the best pickups my ears have heard!
Maybe in the future I might hear a DiMarzio that makes me go "OOOO, I want THAT!" Until then....
why? if that's the case, then why bother discussing any other brand of pickup in these forums. you might as well erradicate all threads that have nothing to do with duncan pups. the question was about which pickup do you prefer and why. there's no bias in it. i personally like both the same.
To be honest, I must say that Dimarzio tech support staff is also top notch, and their descriptions on the website are dead on. The technical information is a bit different (for example, there is no resonant peak, but there is output in mV), so I guess they are more or less equal with SD on this account.
The biggest plus of SD is this forum and you, guys!
I should also add that I like the artistic design of DiMarzio's site a little more than more tech-oriented design of SD's site but that's a matter of the personal taste.
Neither. I haven't had a guitar with a DiMarzio or Duncan in about twenty years.