We recently developed and published a scaleable multi-user benchmark called XMach-1 (XML Data Management benchmark) for evaluating the performance of XML data management systems. To our knowledge it is the first such benchmark. It aims at realistically evaluating the performance of individual systems as well as to allow for a performance comparison between different systems and architectures ranging from native XML data management systems to XML-enabled relational DBMS. Specifying and implementing the benchmark revealed a number of problems which are partly due to the lack of a standardized XML query language, the complexity of the XML format and the relative immaturity of current XML database software. After a brief review of XMach-1 we will discuss our experiences made so far.