The 24 step Gold Point was not working out for me. Sent it back to Singlepower. Mikhail swapped it out with one curved for my equipment and listening preferences. Great now!
The 2c51 adapter with 6bl7's sounded by far the best for me as a preamp in my MPX3. (no power mods for 6bl7's) Huge soundstage and detail compared to 12au7s.