Is it always necessary to have Test Advantage/Infragistics to work with .NET application?

Is it always necessary to have Test Advantage/Infragistics to work with .NET application? Are there any particular reasons why a tester must have it? I'm working on .NET application and sometimes wondering whether it's my lack of experience doesn't allow to automate some objects(for example: tabs on the SwfObject(tabParams) ) or it's because we don't have this additional tool to automate .NET application. any help/advices greatly appreciated