I want to get two monitors for the rear of the car, I have the 701 DSP and can not use the inprint with this on the 9887. The 9861 has 24 bit DAC as with the 9887, but has the optical out that the 9887 does not have. I like the biolite on the 9887, but willing to trade off for furture expansion with the DVD palyer. is sound that much better with the optical? I have heard mixed reviews, from major differnce to not really, whats up?