understand that Lexicon is first and foremost a pro audio company specializing in mixing boards and processors. Meridian is a consumer High-End focused company that has dedicated itself to digitizing everything. so neither is great at preserving the analog signal. my old Proceed AVP smokes both in the analog pass-thru and 2-channel 16/44 processing performance.....but it is really a Levinson 2-channel preamp with a Levinson 2-channel DAC......so it should be better than Lexicon or Meridian.
i also own the Lexicon MC-12 that i use in my Home Theatre room (2-channel performance is not important to me in my HT room since i have a dedicated 2-channel room----where i use a passive preamp). the MC-12 is best at DD and DTS processing; and their 7 channel processing. if your priorities are movies, the MC-12 is hard to beat.....and you don't have to put up with the unwieldy Meridian interface. the Meridian is also a good processor, is a better sounding 2-channel performer than the MC-12 (but still not outstanding) but really excells at DVD-A.....for all the good that will do you.
so it all depends on your priorities and the degree of complication you will put up with.