What’s the best management tool for supporting the support process?

TechRepublic member Stephen Shiller recently dropped us a line. He is in the process of centralizing his company’s service desk by moving its most skilled resources to the contact center. “We currently have LanDesk installed at one of our largest customers. It was chosen by my predecessor, but I cannot seem to find any details in respect of a formal evaluation. I would like to conduct formal evaluation against a short list of products, probably LanDesk, HP Radia, and possibility one other. Do you have any recommendations regarding the above product list (or comments about them) and the selection criteria?”