Interestingly enough I think the majority of layouts on tour at this year's NASG convention will be DCC. I like and utilize conventional, Legacy (TMCC), and DCC on my layout with provision for switching back and forth. Don't have DCS or so far FC. Very much doubt DCS ever, and now that Lionel has signaled more Legacy engines coming, maybe not FC either. But each to their own. They're all plenty of fun. Just that you might want to design your layout with more than one in mind - initially or eventually.
Dave - For Rick's benefit and my interest, are DCC decoders easier to install in say an American Models diesel than TMCC control + sound boards?
Rick - As someone who went through the same decision process 2 years ago, I'd be happy to discuss what I have learned if you'd like.