sokogear, I think you have a pretty good handle on the situation. Never heard one myself so only know what turned up after a ton of research. These things are transformers, very specialized transformers at that, and so they are more a way of tweaking or fine tuning the cartridge than anything else. There are whole websites devoted to the subject, with in depth reviews of far more different SUT than one would think even exist! Never even knew so many were out there until I started digging into it.
This sets up the perfect situation for some to be able to say the SUT is essential and others to say forget it what a waste, and both be right. Because if you luck onto one of them that is really good for your particular cartridge and phono stage then boy oh boy will you be happy. But you could just as easily wind up with nothing or worse, a royal headache.
The sensible approach I think is what Decware does, make a phono stage designed for high output carts, and then offer SUT in various gains to suit different MC outputs. You can also trade them back in for another in case you need to for cartridge changes. This avoids yet another pitfall of SUT, trying to sell for used something hardly anyone wants to buy new. Take a bath, you will!
This sets up the perfect situation for some to be able to say the SUT is essential and others to say forget it what a waste, and both be right. Because if you luck onto one of them that is really good for your particular cartridge and phono stage then boy oh boy will you be happy. But you could just as easily wind up with nothing or worse, a royal headache.
The sensible approach I think is what Decware does, make a phono stage designed for high output carts, and then offer SUT in various gains to suit different MC outputs. You can also trade them back in for another in case you need to for cartridge changes. This avoids yet another pitfall of SUT, trying to sell for used something hardly anyone wants to buy new. Take a bath, you will!