The ability for users to create their own models quickly is great! It also helps that there are multiple versions of parallel domain available so you can make sure your model will work in different versions of pdns easily as well.
I wish we could use other CAD formats than dae or fbx. For example, if someone would like us to simulate using Solidworks instead of exporting our design files from Inventor then this tool does not support solidworks directly out of the box. We have been able to solve problems faster by being able to test designs more efficiently without having to do any physical testing at all!