Audio Note SUTs - Are they worth the money ?

Folks,
I am switching to an all Audio Note system. The preamp and phono stage is M6 phono and power amps are a pair of Conquest Silver Signature monoblocks. I need an SUT for the MC stage to be fed to the M6 phono preamp (it has only MM stage internally). The prices of the Audio Note SUTs have perplexed me a bit. Even an S3 costs a bomb (about $3.5k) for an SUT. Then there is S4, S5 and S8 too. I am not going to use an Audio Note cartridge but rather an AT ART-9. They have a version which matches my cart but I just do not know if the prices are justifiable. Has anybody tried any Audio Note SUTs ? Do they really do anything special to command that kind of prices over other good SUTs around  which are generally quite a bit cheaper ?