A good while ago I bought a set of BK Mules to put in an Epi Les Paul Prophecy plus based on the sound clips and you tube etc. The ideal was to upgrade the Prophecy in all areas (hardware etc), to make a great guitar out of it. When I fitted them the bridge pickup was very shrill and bright (not what I was hoping for). Bareknuckle were very good and swapped the bridge Mule for an Abraxxus. That made an improvement but not enough for me to like it. Tried all sorts of pot values and tone capacitor values but couldn't make myself like it. The Prophecy was sold on, and the Bareknuckle pickups were stored for future use.
Recently I fitted them into a Japanese Tokai LS100 (excellent quality instrument - better on all counts than Gibsons I have seen and owned), and they were outstanding. The bridge Abraxxus was not at all shrill or unpleasant and the combination of Mule neck and Abraxxus bridge worked really well for me.
The lesson learned here is to watch out for the pickup spacing when choosing pickups. The Prophecy was 24 fret - to get the 24 frets into the standard scale length the pickups were closer together and the bridge pickup was closer to the bridge than a 22 fret version. The close proximity of the bridge and its pickup led to the over bright sound. On the 22 fret Tokai they sound fine. In fact better than fine!
The critical spacing seems to be the distance from the bridge (of both pickups although much less of a problem with the neck p/u) and the distance between the pickups.
