Dependency Injection for WCF: Should I use Contract Behavior or Service Behaviors?

Question

According to MSDN http://msdn.microsoft.com/en-us/library/ms730137.aspx, Contract behaviors (IContractBehavior types) enable the customization of both the ClientRuntime and DispatchRuntime classes in client and service applications, respectively.

When we are implementing DI in WCF, the container should be created per user or session, right?

So, I think Contract Behavior might be the best suite.

But when I'm going though DI in WCF articles on the net, I found that the most of people are using Service Behavior and some are using Endpoint Behavior..

What behavior should I use if I want to use DI in WCF?