It is of course a crap shoot. I would think that eventually all the PC modules will come w/ SONAR - if not X3 then 3.5 or 4. That has been the history of Cake plugs, both effects and synths. So it depends upon how long you want to wait.
The CA-2A is great. The SSL stuff is good - the gate works well tho I don't use gates much. The rest of the ssl channel works and does so dynamically as far as hitting it harder. Some (esp. older) software has the color or sheen or whatever that seems to be tacked on whether you hit it hard or soft. I tend to use the softube FET or the CA-2A for 90% of my work, tho. I have the limiter but don't use it much - I'm used to Voxengo's elephant. But everybody seem to love it here.
If you don't have any higher end plugs and want some - it is a good deal and useful. Just be aware the ssl channel is likely to come w/ the next paid version of SONAR (it is the oldest). Still a good deal tho for the optical and limiter modules if you don't have other versions of those.
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