Ken Malgren says:

Mike, all DCC decoders are not alike. Functions differ greatly. Some decoders offer sound reproduction, multiple lighting effects, etc. The only way to know is to first read the package to be sure that the functions you want are there. I suggest reading the decoder manual that most manufacturers post on their websites.
Decide what you want from a decoder then do the research to find one that meets your requirements.
Hope this helps.