Much as I love my Kato CB&Q E8/9s, if you want DCC with sound and a mars light you might want to check out the BLI Es.
It is very easy to put sound and special lights into the E8. Need to mill a space for the speaker at the rear, but otherwise there is plenty of room. I just completed this with my UP E9 A/B combo for the CoLA, using LokSound Select Micros in both.