An odd question, but a shout out to any existing Softimage users. id 4 takes two different kinds of mesh formats, LWO and ASE.
I'm doing some work on The Dark Mod (doom 3 modification) and am trying to find maybe something out there compatible with it. Right now I'm using a Blender export workaround to make my meshes work. Currently I'm using the LWO exporter that's already with Softimage 2015. Only thing is it breaks object smoothing as well as vertex paints for the in-game version. So I export in Soft and then do a secondary export from Blender to finalize it. Pretty annoying step for multiple meshes if you ask me.
ASE files are a whole other deal but I haven't been able to locate an exporter for that yet. It may be my best bet if I did but the documentation is far and few these days. I figure it's a long shot, for an old engine as well as an old modeling app but I figured it was worth a try. Any other tips id4 to XSI would be appreciated as well!