I think it's one stupid idea.
Basically you crypt your files and the only way to get it the decrypted is by sending a sum to an address from which those guys take a fee?
Correct me if I'm wrong but from their tiny instructions, this is all I could figure.

Besides, it's not ransomware, it's more like masochistware to me.
What if you need those files urgently and you have no BTC left? 

There are hundreds of ways to secure your files by encryption for free, why would you pay for this?