I've recently purchased a Sadowsky Semi-hollow. The craftsmanship is undoubtedly impeccable, the low register is very warm and resonant and the guitar has great responsiveness and sensitivity.
However, compared to my old Ibanez Gibson ES 335 copy, the unwound B and E strings on the Sadowsky sound a bit thin despite the great clarity. I've increased the string gauge from 12 to 13 (12's sound and feel like 10's on this guitar for some reason), raised the pole pieces, played with the EQ, but still failed to fatten the sound of these two strings. I'm looking for the tone that Kurt has on his Untitled Improvisation video (clear and textured but still fat). In that video, his high strings sound like they have higher tension, and thicker and "grabbier" (I know this comes down partially to technique).
I've gone to the luthier and tried on a few heavier bridges and tailpieces, since the issue was acoustic. They succeeded in fattening out the tone, but also dulled it down. In the end I opted to keep the sensitivity of the Sadowsky tailpiece and bridge.