I tried out the Bluetooth audio between the NW-A35 and my SRS-XB3 Bluetooth speakers. As reported elsewhere in the thread all the sound enhancements don't work over Bluetooth. FWIW, the FM radio also won't work over Bluetooth. The volume control on the player adjust the volume on the Bluetooth speakers showing + or - on the LCD display, but the numerical scale is not displayed playing back over Bluetooth.
I have the player in a Sony CKS-NWA30 case. I like the case. It would be nice if the display turned on when the case was opened, but it doesn't do that.
The host PC can read from the player's internal storage at ~28MB/sec over USB. Copying to the player's internal storage is ~26MB/sec over USB. So it pretty much maxes out what USB 2.0 can do. I haven't tested a microSD card yet, my 200GB Lexar was bad.