The best place to ask would be over at the
SCAL forum. That said, SCAL 3 supports the Cameo. So you should be able to keep working the way you always have.
I have SCAL 2 and use Inkscape quite often with the Cricut. I've also played around with the Silhouette's software to get a feel for it. Inkscape remains far more powerful than SCAL or Silhouette Studio for drawing.
I wouldn't be afraid to try out Silhouette Studio, you may like the way it does some things. And may prove useful for print and cut. But otherwise, I don't think you'll find much reason to move away from SCAL.