SUT vs. Phono preamp


On what basis is  the decision to chose  a SUT vs. a phonostage made?
boofer
Dear @fleschler  : Zesto is a good SUT but I think has a little " problem :
" extremely-versatile "

To achieve all those settings the unit needs some switches, I can say a lot of them, and the best switch is no switch because degrades the cartridge precious signal information.
All the losted cartridge signal information through those switches never came back ! ! 

No single switch is the best way to go with SUT's. Signal have to pass as directly as it can, with no " obstacles inside the SUT.

That's why the Denon AU-1000 is so great SUT and of course with excellent transformers.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
@rauliruegass I spoke to Upscale Audio who sells the Zesto and he assured me that there are no switches in the impedance changes, they are all done using different taps on the transformers.

Yes, my next cartridge (which maybe the top of the line Benz) will probably have a Zesto SUT to accompany it.
There are so many great SUTs from the past, so it is absolutely no problem to find one and try one (or even a few). 

One of the reason i like Luxman SUT is because i can have 3 different SUTs in one set. Basically two is enough for nearly all cartridges as you can see on that image with 8030 and 8020. However, they made another one (8025 for use with cartridges with impedance from 3 to 40 Ohm). Those SUTs are Silver toroidal type. Instead of changing SUTs user can change inserts in one base. Amazing feature in my opinion. 
I use a homebrew battery ploperstrd tube phono preamp. Undetectable noise floor; twin mono design so no cross talk; and a stepped 4 deck pot with 1% metal film resistors from Vishay I got from Alan online dealer. Sounds awesome. 
It’s a Nelson Pass design using 12AE6 6.3 volt old fashioned car radio tubes. I side a nine volt lithium battery for a power supply;  gives a bit more gain and don’t seem to shorten tube life much, if any. Mine are nine years old and dhow no sings of weakening, at least so far. Really sweet sounding component!