What is the WCF equivalent of the Project Server 2010 API ASMX login method?

So if using the ASMX webservices for Project Server 2010 you can easily check if a user is valid by simply using the following which is great:

                loginWindows = new SvcLoginWindows.LoginWindows();
                loginWindows.Url = baseUrl + "_vti_bin/PSI/LoginWindows.asmx";
                loginWindows.Credentials = new NetworkCredential(windowsUserName, password, windowsDomainName);
                result = loginWindows.Login();

But this is using the older and not as good ASMX web services so I was just wondering what is the WCF equivalent?

Right now I am resorting to doing AdminClient.ReadServerVersion() which works fine (although sometimes hangs for 5-10 seconds) and correctly fails if the user cannot authenticate against the sharepoint project server

               adminClient = new SvcAdmin.AdminClient(ENDPOINT_PROJ_ADMIN);
               adminClient.ClientCredentials.Windows.ClientCredential.Domain = domain;
               adminClient.ClientCredentials.Windows.ClientCredential.UserName = username;
               adminClient.ClientCredentials.Windows.ClientCredential.Password = password;
               adminClient.ReadServerVersion();

Although I am not sure how good of a solution this is.. and I am wondering if there is an actual WCF equivalent to the ASMX login() method or if there is at least a better way of doing it than ReadServerVersion() - keep in mind I don't want the login taking more than 1 second

Thanks!