I own the 12v version of this amp and in my opinion it is outstanding. Mine is slightly modified and I rotate it in my system with a Music Reference RM-10 MkII and Atma-Sphere S-30. The amp performs on par with the S-30, but lacks a little bit of the bass authority in comparison. If you are looking for a reliable SET amp this is a very good option. Unfortunately they are not in production any more and I have not seen any come up used.