[Gray Adams]

Use whatever you can get the most support for. If your mentors or alumni know Solidworks, use Solidworks. If they know Inventor, use that. If nobody has used either, it seems like Autodesk is more committed to FIRST than Solidworks is, and you'll have a slightly easier time getting help from these forums.

But from my experience, and almost everyone else I know, your students will use Solidworks in college. Outside of education, it feels like everyone uses Solidworks, and its better to be able to say you know Solidworks than it is to say you know Inventor. I know there are employers and schools out there that use Inventor, but it just doesn't seem as common.

Either way, the skills will transfer from one package to the other pretty easily. If you can CAD the entire robot in Inventor, you'll be proficient with Solidworks in no time. Just be aware that it may be difficult for the team to switch over. It does take a little bit of time, and you will lose all your old models (importing is finnicky and you lose the feature history). It's hard to go wrong with either, but all things being equal, I would say Solidworks.