Which is better to use to hide using tor vpn or obfs3?

Question

Computer networks

Suppose I want to hide the fact of using tor from the ISP . Which is better to hide the use of tor vpn or obfs3? I think that vpn is the only one I'm afraid that the authorities can monitor my vpn provider or put pressure on him and force him to monitor user traffic. What is the best way to hide the use of tor from the ISP?
Suppose that the traffic of the first vpn provider in the chain is monitored. How will the VPN chain help in this case?