In case you didn't know, those awfully nice people over at Autodesk recently released Inventor Fusion (beta) for Mac. Inventor Fusion being an MCAD application which I think will eventually take Spaceclaim's crown. There are a few teething problems with getting Fusion to accept SAT and DWG files made with any other software apart from AutoCAD at the moment, but Autodesk have assured me that they are looking into this.

I think Inventor Fusion together with Shark/VC could be a dynamite combination to have/own?

It's still in beta, so it will crash. Autodesk assure me that they are optimising Fusion as we speak. I've also sent them ViaCAD SAT files to get them importing into Fusion.

Right now I still prefer ViaCAD, but we'll see how it pans out. :)

The 123D app for PC that Autodesk does started life as an "Inventor Fusion Beta". It did file transfers between Creo, Inventor and parasolid, (nice!)which was trimmed out by the time it became 123D. Autodesk bought a permanent license for ACIS at version 7, but went off with its own kernel after that, so .sat transfers with AutoCAD and 123D, and possibly this fusion version as well, might stand a better chance of success if you export/transfer as ACIS V7.