I've recently been working on digitising my record collection to an mp3 player. Since I don't have an auxilliary socket on my car audio, I decided to get this.
Now firstly, it isn't a full function mp3 player. You can't scroll through your list of albums, artists etc. You just get a stack of songs, in my case I've added 470, although it does play them in album order. Now this is the downside, because there's virtually no way of telling where the song or album you want to hear is. There is a facility to go to specified song number, but that's it. If you want a specific song or even album, finding it is a nightmare.
Now the reason I've given it 4 stars. I am amazed how good the sound quality is. There is a very faint background hiss, but I can only really hear that when the car is stopped and it's a quiet track. For example I tried an Enigma album which tends to range from very quiet to loud, and there was a little hiss, same with the Floyd. However put on the Stones, Rory Gallagher or Robert Plant and you won't notice it, and lets face it, under normal driving conditions ambient noise is more of an issue than a very quiet hiss.
I was also suprised when I turned the engine off that there was a radio station sharing the frequency I was using (not very strong admittedly), but this unit had been totally unaffected, although it may have been the cause of the hissing? I'll need to experiment to be sure.
One thing to be aware of before buying, it won't take a storage device greater than 4 gb. Not a major problem since my 470 songs only take up 2.3 gb, but if (like me) you were planning on using an 8 gb SD card, you can't.
Overall, before buying this I did have misgivings as to what the sound quality would be like, but I shouldn't have worried. More mp3 player options would have been nice, or even a jack plug so you could plug in your mp3 player, but at this price what do you expect?