I sold the O2 to fund an Asgard 2 purchase (which I hated). No clue why I did that..in the end I just ended up with a new DAC . Should have just kept the O2 since it was for my bedroom setup.
I was stupid and wanted slightly smoother treble. We're talking like a 3-5% improvement for long listening sessions! Can you say nit-picking?
Well, the JDS Labs O2 is only $130 now, a little cheaper than when I first bought it.