I am new to Sonar. I have used REAPER (sold it), Presonus Studio One (sold that when I the next one) and currently Cubase (for the past year and a half). Don't get me wrong, I love Cubase, but it lacks some basic features for being such a powerful program. Not to forget that I'm not crazy about the way it handles comping and takes. I don't like any of the included effects with Cubase, except for Room Works.
Sonar seems to have some great tools for mixing (and recording too) and that's why I've gotten it. :) I'm on Sonar X3 Producer, by the way.
I was also looking for some tutorials, so this thread is great. :)