I use the following vintage style strat pickups: SSL-2's, APS-2's, and Antiquities.
First of all, a little background.
I'm a blues player. Although many of the tunes I write are more pop than blues, often when I play, the blues is there in some form. I’ve played 40+ years, played in bands through high school and after, but play at home now. I most often play strat type guitars through small Fender tube amps – usually a Blues Junior or an old tweed Deluxe. Since I don't play out, keep that in mind, since many players comment that when playing with a band, their guitar sounds different, or doesn't cut through as well.
My favorite tones are a neck or neck/ mid position on “10” through a driven tube amp, but I love to be able to back off a little on the volume for clean chording, usually on one of the other positions. I often try to set my guitar and amp on the edge of natural distortion, and control my tone with touch dynamics, so that I can almost go from clean to overdrive with just my right hand attack.
I have three strats with Seymour Duncan pickups - a '94 G & L Legacy with SSL-2's (stock), a custom strat with APS-2 mid & neck/ SSL-3 "Hot" bridge, and a custom strat with Antiquities. These are all alder bodies with maple necks and rosewood fretboards.
The Duncans, in comparison to other pickups, are kind of like a sports car compared to a regular sedan - better performance and handling.The Duncans have a smoother transition into distortion, and just get there easier, without any ragged edges around the tone. They have a sweeter singing voice, with a vocal quality on the notes when pushed, and are clear and clean when you back off for rhythm playing. They are a "player's pickup".
The SSL's are a terrific vintage style strat pickup with nice articulation and dynamics, soulful and punchy at the same time.
The APS's are even smoother, and a little more compressed. These pickups were a very pleasant surprise for me, and have become my favorite. The APS in the neck is about the nicest tone I've heard in a strat. It has a big warm tone, but still retains articulation - especially nice for soloing.
The Antiquity strat set is very special - simply one of the nicest set of pickups there is for true vintage tone, but better! All the pluck, ping, and quack of a vintage strat, but because they're wound a little hot, they have a nice, smooth, purring ovedrive tone. The Antiquity set, with Texas Hot neck and mid/ Custom bridge, really deserves special recognition for its calibration - the Custom bridge pickup, wound at around 9.7K is a big improvement, and overcomes the weakness strats have - weak bridge tone.
This brings up another point. I agree with those players who prefer a hotter bridge pickup in a strat. My Legacy has a stock calibrated set, and I seldom use the bridge position. My strat with APS's has a great hot rodded sound with the SSL-3 "Hot" in the bridge. I also wire my bridge pickup to the mid tone pot, so I can roll off some treble.
Here are a number of clips to illustrate the tone of these various pickups:
Legacy with stock SSL-2's:
http://www.bluestheater.net/orange.html
Custom strat with APS-2's neck and mid/ SSL-3 "Hot" bridge:
http://www.bluestheater.net/placida.html
Custom strat with Antiquities:
http://www.bluestheater.net/bluestrat.html