I have the AKR02 and I like the detachable cable, but it is a proprietary screw-in connector. I have emailed iRiver several several times about the availability of a balanced cable for use with the AK240 and they don't even bother to reply. I also asked about buying the balanced cable for the AKR03, since I already have the Roxanne UF and an AK240, but again no reply. Not exactly a responsive vendor.
They still haven't fixed the AK100 software so that it can play a VBR MP3 track all the way to the end.