Since the "old" RCD 300 MP3 is not enabled and an aftermarket radio is simply too expensive and uneconomical, I was looking for MP3 retrofit solutions and am stuck with ARCS.
Internet research revealed here consistently positive experiences with the device.
Only during installation - or disassembly of the panel in order to get on the radio and its connections, it still needs more precise searches and n few quiet minutes of incorporation.
Ultimately, the installation worked perfectly and the device does exactly what you expect from him.
Currently a 4 GB USB stick is connected. This works fine. Title search goes ruckzuck, switching radio - MP3 takes no pause for thought and what's really great that is "Memory function", ie, the device remembers the date on which the played MP3 song was after ignition or radio mode.
The only downside: Removal / Installation Introduction is not included and a manual you have to rather tedious search on the internet.
The expansion is not without (here can abort plastic snap etc.), but what ARCS nothing can. But rebuke to VW (so is the anti-theft radio quite well ;-)
An illustrated SPECIAL installation instructions would be here the "i" -Tüpfelchen. (Hence deduction of one star)
But otherwise an absolute buy recommendation!