In short, the devices are completely unsuitable for me, and for the following reasons:
There is no way for playlists, so I had been thinking about some different microSD card with eg only 2GByte to buy in order to allow for different environments / times of day / moods matching playlists in the form of the available music tracks.
MP4 Player Portable:
The musical enjoyment is diminished by high noise level to impossible.
The device response to inputs is sluggish. The menu structure is not well thought out.
Since shortly after the first few uses of the player will constantly new, ie the unit is not (more?) Operational.
Mini MP3 Player:
The small player is booming: If the flashing LED (indicates the flashing, that is played) is just out, I hear a humming sound from the headphones.
The Earphones I had not been tested.