Do you have LP's? Is that why two channel pass through is important?
Because otherwise the DACs in the Prepros are likely better than what is in your DAC or Cd player.
Two channel is inferior for Redbook CD playback anyway in my experience.
In less than a month I am going to Chicago to compare the EMM DAC6 and the TAG McLaren AV192, the person who owns these devices tells me there is very little difference between the two on Redbook CD in two channel. He prefers TMS to either two channel options. So maybe your compromising your 7.1 channel to accomadate your 2 channel.
A foriegn thought on this site for sure.
Meridian Surround Processor, its the only choice, until TAG McLaren Processors are resurrected as AudioLab.