SIA has a huge head start, and a really involved community. Really great dedicated developers.  They don't have anywhere near the cash of filecoin (wtf was their ICO about, ridiculous).  File coin will definitely have an accelerated development, in the meanwhile SIA is already a working network and protocol. The API tools to integrate it into other services are half way there as well.

We will see what the economics of it are as an investment... but it will definitely be a better investment than that over bloated ICO of filecoin, until it crashes a little.