I currently own a Micromega Mydac and a Musical Fidelity V-Dac 90. The Mydac is the more musical of the two, when its usb input is used. I have been trying to replace one of these and have tried the Topping E-30, SMSL Su-9n, iFi Zen Dac Signature, Cambridge Dacmagic 200m, Geshelli Labs j2 and...