I love the sound of my recent upgrade to a Koetsu Rosewood Signature Platinum through the Sutherland Duo. This does need a fairly high mass arm, I added a 3gm weight to the JMW Memorial unipivot arm on my elderly Scoutmaster.
Superb resolution, gorgeous mid-range, excellent treble and bass. The bass was ever so slightly wooly without the weight. The upgrade from the Koetsu Black was far greater than I had expected.
Sutherland now have a range of "current mode", transimpedance phono stages, one of these may be a fabulous pairing with the very low impedance (and output) of the Koetsu. I am contemplating trying a change to one of these
The Loco is available at a discount from Upscale Audio, but note that this product requires balanced input and thus a new junction box on the TT and XLR phono interconnects. There are other Sutherland transimpedance stages that work with RCA cables.