I don't have SDE but I know you can do rhinestones and import SVG's. I saw a video where there is a really nice eraser in SDE so you can have finer control where you erase your designs. I remember something about better sketch tools.
I don't use SDE because I learned my Silhouette "old school". I do all my designing in Inkscape. I then import my designs in either PDF or PNG and let the Cameo do all the tracing so I can fix any node errors before cutting.
I like my eraser in Inkscape.
Rhinestone feature- I use MTC with my Gazelle so I just use the rhinestone feature in MTC.
This wonderful lady has really great tutorials for SDE- http://www.youtube.com/user/doodlingdebbie1
. Reason I say she is great she is one of my friends on the former pcCrafter board.
Even if I didn't know her I would highly recommend her videos. She puts a lot of work into them. I threw in her videos because I know she goes into more details what SDE can do. I thought it would help.