For your $79/99 you don't just get a re-badged Rapture. Rapt, IIRC, used less than half of Dimensions engine, playing back a wavetable of the sample. Dimension plays back entire samples, too, which is why it was used for acoustic emulations (and has the library to support it). Rapt was geared more toward electronic instruments, and I had an ah-ha moment when I discovered Rapt. was where most of the organs lived, not DimPro. Speaking of libraries, Rapt 2 has about 3 gigs more of samples than Dimension (the original Rapt had a small library since the samples were snippets useful for wavetables - 3000 sample length I believe. 3 gigs aren't much in these days of mega libraries - I'm sure someone has put out a 3 gig collection of triangles by now - but done right and for a specific synth can make a whole new synth. See Kontakt and the libraries sold for it. NI doesn't buy Heavyocity products and give them to Komplete Plus owners. Or the new synths they develop for REaktor.
And that cost is before you get into the performance additions - x-y pads and mixing. And who knows what else?
If that ain't enough to lay out money that is fine. As I said earlier, just wait, not doubt it will be had for free one day. But no way is it a "fix" that needs to be included with SONAR, which the last time I checked was a DAW for recording soft synths, not a soft synth itself. Just the same as the original Dimension (not Pro) came with the P5 DAW and was an integral part of the sale. When they upped to DimPro and added to the library, guess what, Cake released DimPro as a stand alone product. They didn't give it to if you had P5 (in fact, they killed off P5). You can usually tell if someone is trying to sell you something new if they give it a new name. Cake is just following well-established guidelines.
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