Yeah its a scaled down version of a commercial product from Autodesk, those people that make Maya and 3Ds Max. It has be compared to Maya with it's power. The full version of Softimage when it was owned by another company called Softimage (lol ) was used to create Half-Life 2 and the program has been used in several movies, my favorite one it was used in was the 300.

The scaled down version can export to .collada but has a polygon limit of 64000 polys. for games that's okay, in a model you may use like 6400 but not 64000. rendering is also restricted. It has documentation with it so tutorials and books aren't necessary, you just have to experiment. Besides, all the books that are out for softimage are out of date and there are almost no tutorials anyway. :E

here is the link to the web site, it's a really powerful tool that should go good with this engine.

though, this is very old news...it worth mentioning.

besides, the poly count limit, there is also texture rez limit.

There is also free DT tutorials that are free to download from their website...so, it worth checking.