I'm undecided too, and that's the only ICO I've seen that I consider possibly legitimate.

IPFS itself is supporting evidence - it shows that those people can create a working and actually useful product. Filecoin seems like a good fit for the "incentive layer" above IPFS, and from what I remember from the ICO, they did their best to make it legally in the clean.

I guess we'll see what happens when (or if) Filecoins get released.