Situation: We were using the open-source product "Request Tracker" but we had just had our Perl develop retire and the system did not give us the management information they required. We needed a system that was easy for end-users and would fit into our system with minimal management overhead. HarePoint Helpdesk ticked all the boxes for us and end-users love our ticket system now.
Result: The new ticket system gave us what we needed in management information and user interface. It fitted into our SharePoint estate and the support teams capabilities.
Bottom line: It now far easier to see where we need to put more support and where we have too much. It has also enabled us to build a business case for another body on the team, All of this in just a few months makes it a very effective tool for my team.