I have been swapping pickups for years. The first pickup upgrade was a SD original "Trembucker" (the one with the double poles). I remember at the time it was hotter than the pickups that came in the Charvel, created more distortion, and I liked it better. That was back when amps didn't come with much distortion and you had to use a boost or a distortion pedal. Of course Metallica was big at the time, and they used EMGs, so that was my next upgrade. I honed my soldering skills wiring the EMGs into a number of guitars. They created even more distortion and were easier to play. I had been playing for about three years, and I remember I had a hard time playing guitars that didn't have EMGs. I used EMGs up until about the 5 year mark. Around this time, amps were coming with more distortion, and I realized that you didn't need blazing hot pickups to get metal and lead guitar sounds. So I entered into a long "tone phase", where I was choosing pickups based on EQ and "feel". Over the next 15 years, I probably tried 40 different humbuckers. A handful of SDs, but mostly Dimarzios. I think I tried almost the entire Dimarzio catalog. Why Dimarzio? Because they were $10 cheaper than Seymours and most of my guitar heroes were Dimarzio endorsers. After a time I gravitated to the Norton and Fred pickups. They were more "toneful" and had a "bigger" sound. (as medium output pickups with lots of presence do.) I thought the Norton was my holy grail sound. Then I thought the Fred was. After about 5 years with these, I realized they weren't the best for speed picking, I was willing to trade some "tone" for tightness and clarity. So I upgraded to the penultimate pickup; the Dimarzio Evolution. These were "dual resonance" design like the Norton and Fred (so you *know* they are toneful), but hotter. I used the Evos for about 5 years and swore by them. The SD Full Shred also gets honorable mention; I had a guitar with a Full Shred and it was very similar to the Evo. About five years ago, I was bored and picked up a Chinese super strat. I wanted to see how a Floyd Rose (special) compared to the Edge and LoPro trems I had been using for years. This guitar was an eye opener. For one, I quickly got used to the Floyd Rose, and while there is some brushing against the micro tuners, I much prefer the Floyd Bar position and its screw in bar that lets you adjust the tension. With the LoPro trems, the push in bar, the bushings would wear thin, so I would always be taking them off and painting the inside to make them tighter (trick learnd from Ibanez Rules). Secondly, the stock pickups in this $250 guitar were quite good! They reminded me very much of the Duncan Full Shred and PAF (in neck). I figured they were clones of these designs. Not wanting to leave anything on the table, I decided to try one of the Dimarzios I had not tried before. A Dimarzio D-Sonic. My thinking was that if I didn't like it, I could return it and get a Norton (so I would have a guitar with that old favorite.) Marco Sfogli had used this pickup and I also understand Petrucci used it too. I absolutely LOVE the D-sonic! It has a really thick presentation with plenty of harmonics but the bottom is tight. In comparison to the D-sonic, my Evo guitars sounded "thin". They were missing the thickness in solo notes. Now whenever I plugged in an Evo guitar, it seemed to have an over abundance of harmonics and was "washed out" sounding. (not as strong fundamental tone.) I realized the D-sonic wasn't a "dual resonance" design.... and this got me thinking. At this point I had a few Evolution guitars that I didn't like playing because of the pickups, and I needed to do something about that. I looked through my parts box, to see if there was anything I could use as a stop gap before ordering $500 in D-sonic pickups. The only answer that presented itself was the Quantum pickups that came in a couple of my Ibanez guitars. I remember I thought they sounded OK, but they weren't dual resonance, and didn't have much harmonics compared to the Evos (I used to use harmonics as a barometer for how good a pickup was.) So I grudginly put the Quantums back into a guitar to see if I liked them more than the Evos, some 20 years later. Wow. Just, wow. The thing is, the Quantum pickups sound almost exactly like the Dimarzio D-Sonic! They have a tight bottom end, a thick mid, but with perhaps less harmonics. They have about the same output and same drive characteristics. Overall, they are a perfect stand-in for the D-sonic, in a mahogony guitar with a brighter top. When I plug in the quantum guitars, they are interchangeable with the patches I have designed for the D-sonic. Its interesting to me, that after a long journey with pickup swaps I arrived back at the stock pickups. (This after many years of playing and tone tweaking.) Now I care more about switching options and how the coil split sounds, being able to also get good clean sounds. Most of the pickup swaps were done to cure temporary boredom and out of a lack of knowledge. I've learned that alot can be done with pickup height, switching options, capacitors to alter the output or EQ of stock pickups. Stock pickups these days are no better/worse than aftermarket. The advantage of using replacement pickups is that at least you know what they are and have an expectation of how they will work. When I was younger, I fell prey to "marketing" and that there was always "something better". I wanted to distinguish myself. When you find out that your favorite aftermarket pickup sounds functionally identical to the stock pickups, it changes your perspective.