At this point I would have to describe the Onix as "uninvolving". I've swapped it out with the modded Toshiba several times, and each time I find myself drawn into the music with the Toshiba and distracted by the Onix's two dimensional presentation. For those who are unfamiliar with the Toshiba mod, it taps into the circuit immediately after the DAC (removing the filter and analog stage op amps from the signal path) and reroutes the signal to a pair of RCA's through high quality capacitors. The Onix came with an OPA2134 set, which is considered good and offers the quality that's typcially heard in "budget" (under $3,000) players. I've ordered a set of the more expensive OPA627s, which would be used in only the most expensive players. These are single opa chips so they require an adapter board which I also ordered. Somebody on another forum did this upgrade and said that the sound stage become more focused and the instruments got more separation.
In the meantime the Onix sounds very good as a transport for the external Scott Nixon DAC.