Codenomicon is a good tool. It is used for network protocol implementation testing, to find any Zero-day issues, vulnerabilities in XSL. It's an excellent tool that has its advantages and its limitations.

Presently we are using Codenomicon Defensics for a few suites, only for testing. we are doing few open floor tests. Nexus is the one which we will use for European testing. For US usage testing, we will use Codenomicon.