MAybe a stretch on portable, & definately unhelpfulSince since of you are considering the Edirol; if you want a portable (quality) player, with a digital out;
at 1.4kg the Nagra LB (with Digital output XLR AES-3, 24 bit or 16 bit, whatever that is) & USB. While the Sony PCM-D1 weighs only 525grms has Optical Digital Out & USB.
Sure both have some extra hardware & functions you may not want, but then so does a laptop.
Actually the Sony PCM D50 is a bit more affordable, & also has an optical out...