I just want to concur with some of Pappucho's comments on the differences between the 515 and the 321. I too enjoyed listening to the 321 as a portable. It has a satisfyingly wide and open soundstage like the 211 but with a somewhat fuller, richer sound which was noticeably more satisfying to my ear.
And it does indeed seem that the 515 is more detailed than the 321. I would certainly not crown the 321 as my best sounding PCDP. I am actually learning that each of these players has a place in my collection and that which one sounds best will depend a great deal on the headphone, music, and amp, if applicable.
In some ways, the 515 is my favorite player, despite the shrill character of its headphone out. The sound is just very interesting and exciting. The 311 may be the king of tonal neutrality but it's payed for with a certain "greyness" that Duncan has alluded to. This can be compensated to some extent with the first level of Bass Boost, which can add a bit of zest, just as the first level of DDS dynamic range compression can shave off a bit of the shrillness from the 515.
The 321 was actually the first PCDP I had heard that sounded clearly better than any of my DAT players. Along with the 515, this is definitely a player that I would like to mod, by increasing the ESP memory to 10 seconds or more. Obviously, given the price difference I will start taking apart the 321 first
. I am a bit saddened to see the prices for this player rise, but OTOH, I think it does deserve a bit more respect than it has been getting. I will be quite interested to see what the repair estimates are going to be on my players.