I had both of these units made for me and I have waited almost two months for them to come in. I must say I could'nt be happier with the way they turned out. Both have sound decoders in them, the only down side I can say about the MRC sound decoders are the LED's, they have a bluish tint rather than the bright white LED that the Digitrax has. However, in spite of that they are working well and I am still messing with the functions. As you can probably tell I am currently building my layout and the track you see is only a test track. I have almost completed a track plan that I think I can settle on. I will keep you updated as it progresses