Hi MUDGEL, nice to see you here.
I am an old Sonar user myself, and made the final jump to full Cubase in April this year. Until then I was primarily using Cubase with Sonar as third (I am using Ableton Live too) DAW (well - I use Wavelab Elements too). I have not tried DP myself, because I heard the older versions where not that stable and easy to use. That seems to be improved now. Still - the Cubase/Live combination is all what I need (and more), so I feel no urge to dabble around with other DAW’s. Maybe sometime on a rainy and slow day? Who knows…
Anyway - The forum here is not as lively as Sonar’s forum, but it’s not bad either. People here are most times visiting to asking questions or report errors (or perceived errors). In a lot of cases those problems are solved fast by the helpful other visitors here. It’s just not really a “chatting” forum, like the Cakewalk forums, but by no means bad.
Anyway - If you have questions about Cubase, or problems with Cubase, just come over here and ask away… 
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