Thanks to all those who responded about the smoke generators. I am going with the MTH K4 and I hope it will work out. I also may try to install a DCC with sound module myself in a new steamer which already has the smoke generator.

I have been unable to find a steamer with both smoke generator and dcc (with sound).
Can a steamer with a smoke generator be upgraded to DCC?
If the smoke generator bypasses the dcc decoder and runs off straight track voltage will the smoke generator burn out?