Hello,
I used the new Catia X-Design to design a simple plastic part and analyze its demolding and joint line. For someone that uses CATIA V5 every day, I found the modeling not very easy without the boolean operations (maybe i didn't discover it yet). But since it was a simple part I managed to design it with the main features (Extrude, Draft, Filet). The visualization tools are impressive and it gives you many options to visualize your product. But I still think that is closer to Solidworks than Catia.
These are the photos of my first mechanical part on X-Design