I have 16 channels worth. You can read about it
http://www.krashjones.com/pm1000/I don't have a Neve or API or whatever other high-end pres. We do have Drawmer 2-channel but I have not done a head-to-head comparo because since the acquisition of the studio that got us the Drawmer we have had the studios dismantled while we build out our facility.
The pres are colored... hard to describe exactly how, it's not an easy-to-put-your-finger-on kind of thing. For example, comparing connecting my GigaStudio rig to the recording computer, I can go one of three ways:
1. SPDIF_out -> SPDIF_in - this should be 100% transparent, right?
2. TRS_out -> TRS_in - should be nearly 100% transparent
3. TRS_out -> PM1000_strip -> TRS_in - should be the least transparent
Of the above, #3 sounds best by far. #2 sounds worst.
PM1000 kind of "glues together" the bottom end... I don't know how else to describe it. It's kind of like the bottom end is more controlled and focused. In one spot. Doesn't crowd the other instruments. I know this makes almost no sense.
PM1000 also adds some kind of airy, open top end. It's not any brighter. It's just airy. I am sure it's 2nd order distortion.
In all the sound of my pianos (Black Grand, for example) from giga sound more tactile, like you can reach out and touch them, when run through the PM1000.
It doesn't color like you'd expect a "vintage pre" to color. It doesn't have that midranginess, ultra-lush, warm kind of sound that seems to be popular for "vintage" type pres. For example, the Drawmer sounds this way. Larger than life you know. Hyped. Well the PM1K is not larger than life or hyped at all. It's more comfortable and familiar. When I track a lot of instruments through it and then mix together, they all kind of have this "space" around them that makes them play in the mix together much better than what I get from regular console pres like you'd find in a Mackie.
The EQs are very useful, particularly for instruments (never tried them with vocals really). Drum kit, bass, electric guitar.
FWIW, we have insured my 16ch PM1000 rig at $10K. I am sure it'd cost at least that to replace it with 16 channels of something coming nearly close.