This preamp is a very worthy vintage 73 style unit. I've just been through a wormhole of buying, testing and returning 73 clones (3 units in total in the past 6 months, including the current "official" two-channel one), they were all either beautiful sounding but too noisy or just cramped sounding, a little bit "nasal" and tending to distort.
All this changed when I decided to A/B the last one (the "official") against my 73 jr2 that I've had for a while. The heritage offering just incredibly had more headroom, less noise for a similar amount of transformer saturation, and sounded in general more open. Me and the singer singing through both of them instantly prefered the Heritage over the other one, so in my quest for 2 channels of 1073 style pres I just bought a second one...
Granted, if you factor in the price of the rack and the unit's price it's not a cheap stereo pair you're getting, but after a while and several recordings, this unit keeps finding its way into my records.