As far as I remember 4mic from coresound is everybit as clean as sounddevices, and a lot cheaper... so you might want to check that out. Apart from that, I think that if you go with the PdAudio set up you might get a nice surprise somewhere down the lane, namely TC in and out. As far as I can recall, the reason TC could not be implemented in the mic2496 was because of it only had two channels. The 4mic should at some point be able to do two-channel TC. At the same time it can be plugged into a sounddevices making it a 6 channel recorder.
Gordon gidluck is writing software packages and he is making a program called movie2496 for movie recording