I got my Abraxas set a week or so ago, and thew them into one of my M2s (an alder/maple bolt-on superstrat), replacing a set of A2 Stormy Mondays. I loved the SM set, and only had a few gripes with it: the bass was too flubby, and the bridge was too wimpy. I have to admit I had a bit of an "anti-honeymoon" at first, because I found the bridge and neck sounded less similar than in the SM set, (not surprising considering the SMs are 7.2k/7.8k, and the ABs are 7.4k/14k). That was off-putting because I'm really fussy when it comes to neck/bridge balance. However, after playing around with pickup height, I managed to resolve the issue, and the pickups work beautifully together.
The Abraxas neck is sweet like the Stormy neck, but the bass isn't flubby like A2, and nor is it boomy like A5 can be. The treble is a touch less rounded than in the SM, but that actually increases articulation and makes the neck more usable.
The Abraxas bridge is less thin, more compressed, and beefier than the SM bridge. It has a slightly less PAF vibe, I guess thanks to the extra compression, which at first made it harder to balance with the neck, but now makes the set a whole lot more versatile. I don't find myself favouring the neck pickup nearly as much as I did with the SMs. The overall tone is articulate and balanced, and definitely more "smooth" than "dirty" to my ears. Where a Nailbomb roars, the Abraxas howls.
Now that the set is properly balanced, I can select the neck and have a sweet, round but articulate PAF tone, or I can flick to the bridge and have a brighter, equally fat but tighter, more modern sound. However, they don't sound worlds apart: the bass and mids on both pickups are literally perfectly balanced, and changing to the bridge sounds like you've just added a touch of treble and gain to the neck pickup.
All in all, it's a wonderful, versatile set, and ny best BKP purchase yet. I would probably even get another Abraxas set instead of a set of Mules if I got another LP (and i was in love with the Mules I had in my old LP). IMO, the Abraxas set is perfect for my style, which is mainly slow blues, ballads, atmospheric stuff, etc.