Help finding tool that tests web services....

Hello!

For about a week now I have been researching tools that would help me in testing web services. So far I have research SoapUI, Test Studio, tools within Visual Studio and various others but none seem to give me the results I want. Here is what I need it do be able to for example:

1. Test capabilities using Exchange 2007 user add/view in the lab environment.

Now I am able to use tools that bring up the information but not really doing the following once I can access it:

-setup endpoint
-randomize or change data inputs
-assertion support (example: if response is false/fail, is there logging visibility)

Any ideas? I am still doing research so if you have some tools that worked for you or others I can and will definitely check them out!

Thanks!