I have had the S2 burning in all day yesterday, and just took a listen with my Serial's hooked up, and man o man this little dongle is insanely good! I am actually quite stunned by how amazing the sound is from top to bottom, and the staging is fantastic as well. The S2 is freaking legit! This is my first Lotoo product, and with what I am hearing from the S2, I know for certain this will not be last.
The S1 was my first Lotoo product which led me to buy its Titanium dap next, then the S2 when it was released. The tone is so beautiful to my ears.