Multi-CAD is a long way from ever being "solved". Traditionally CAD Vendors have done all that they can to lock companies into their world, and even when they've succumbed to moving to providing good interchange/neutral formats they've often done so in a proprietary way (think .JT, 3DXML, DWF, ...).
PTC at least seems to be finally be coming around to the idea that it makes sense for them to intelligently import CAD data from other packages, and then even better, support change management processes (eg. if it changes in the other CAD package, refresh it in your CAD package). Let me just say "Finally!" :-)
The truth is that essential no global manufacturer can solve multi-CAD, it's a fact of life. At some point one of your suppliers will be using a different CAD package, or someone will need it in a different format. So face this reality and find software and setups that support this.