I also will be switching to Samplitude, although, as Bapu, I did also
opt in on S13, and already had several more to boot. I don't see
Gibson allowing Sonar to be sold, in whole or in part. They seem
to excel at "killing software". So that's the main reason.
I keep my system updated, and eventually, because of that, Sonar
will probably, at some point, cease to be viable, and the lack
of further updates, as things progress, will also eventually render it
obsolete, which is quite sad really.