I used the M2Tech hiface for about a year, and realized that while very good I could get better sound into my old dac. I've since upgraded to the M2Tech Evo combined with a linear power supply and couldn't be happier. I run ST glass from the Evo to my Levinson 360s which sounds great. But that being said I haven't try any of the other converters out there, and there are many.
USB to SPDIF Converters
There are many on the market now.I have a Hag USB .I would like to hear your experiences with these devices.I would like to upgrade soon,to include Hi Rez downloads ,which means getting a different DAC and converter .