I've had this preamp for awhile, never really used it though. I have a focusrite 18i20, this preamp, and the same model with the VU meter.
I tested this out with an SM7B, does not need phantom power. The signal you get from this is trash. Lots of garbage picked up from the tube, specifically the hum, and the gain needs to be picked up an incredible amount to get an audible signal. See the video below on youtube I came across before thinking of pairing this with an SM7B.
Search Art Tube Pre amp/ Sm7b/ Tascam us-1200 (Review) by the vex project on youtube for a demo.
This was nice for an SM58, don't be afraid to spend more money for good a good quality signal.