Purchased NWZ-S739 from him. Dealt less than an hour ago...
Nice sound, active noise canceling works well. I had my friend tested while I was driving on highway, and he said the noise canceling feature shields the wind turbulence noise a lot. Personally tested in McD, it shields distant noises, but random noises from the next table weren't canceled by a great deal. But that was before I noticed the noise canceling sensitivity adjustment. After some tweaks, it works considerably well in my house. I can barely hear voices of my housemates.
About sound quality, it's comparable to my previous higher-end player *keeps secret about what player was that*. As usual from Sony, heavy bass can be expected from the earphones that it comes with, the treble is fine, but could use some improvement. But hey, it's a Sony!

As for the seller, great patience, nice to talk with. And we got to meet in just about after 1 hour of arrangement. Speedy service!
There are still lots of function that I haven't tried of, but in general, it's a gadget that musn't be missed by audio enthusiasts with tight budget! ^^
Thanks bro for the nice player (though I still have to pay for it =P). Free ads (and bump) for you!
EDIT: There are always surprises when you use new player/earphones. I have heard something I have never heard before from it!
This post has been edited by Futamaru: Aug 6 2009, 03:01 AM