If I needed lots of channels today, I'd get an RME Digiface USB. Simple box, around 500$ or less. Gives you 4 ADAT ports in and 4 ADAT ports out. Combine it with 4 Behringer ADA8200's and you have up to 66 I/O.
It brings you RME's drivers, TotalMix and Digicheck.
http://rme-audio.de/products/digiface_usb.php
With USB2 you can have 32 channels coming in and 22 channels out.