There are some professional reviews of this preamp available online. The most usable I found (for phono) is the
Stereophile review by Art Dudley. Dudley is very much a moving coil and tube guy. His reference is a Shindo Masseto all-tube preamp that retails for $13,500. In spite of this frame of reference, once the Parasound broke in, he was very complimentary of its overall sound, speed, and clarity. Having recently moved to an all-tube hand-wired phono stage myself, Dudley's assessment is high praise for a $1K SS unit with built-in phono, DAC, and bass management.
As for the phono stage, he liked the MM section a lot, but found the MC side to be adequate but not great. However, when he used an MC cartridge with his step-up transformer into the MM input, he liked the sound *a lot*. Dudley's step-up transformer probably costs several times the price of the Halo P5. But what that means is that the MM input is very good and noise-free. So if you're using an Ortofon 2M Blue or Red (or whatever's installed on the Carbon these days), the P5 should be an excellent match.