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Yes Siacoin is better in this aspect using the mining model, pays as is used and has its own smart contract's which I believe storage deals can be made between stoarge providers and consumers.

There is a possible sceanrio with Storj, if all user were to leave network it would cease to function but that is no longer a problem due to the amount of users and storage providers combined at 43K and with the new user base on Ethereum is a very unlikely possibilty.

I'm currently testing siacoin as well for whatever storj doesn't use. I can't wait till maidsafe hits alpha 2

Maidsafe does look like a good product one problem is the fact they don't use blockchain, this could lead to a lower level of security vs blockchain storage but will remain to be seen and won’t really be fully known until is released at scale.