I just demoed the PM3. Really nice. Very smooth, big scale sound. Very impressed. This was out of Hugo/Dx90
Did you try the HA-2 with the line out of the dx90? I was happy for Oppo on this new product, sad for myself as it noticeably improved sound over HO on my dx90. It was the first time I tested a separate component in my audio link.
The pm-3s sound and look very promising too, so much so that I have them on my shortlist of portable headphone purchase.