Discovery systems consist of an intuitive search interface and a single central index that gathers metadata harvested from various sources. They offer a unified search environment that allows library users to search at once through all the content to which their library subscribes, and more. As such, discovery services have a great potential as an alternative to stand-alone databases. This potential is what this paper has been trying to evaluate by using the version of Primo Ex Libris (Oria) implemented by BI Norwegian Business School. Due to the size and coverage of Primo’s central index, users risk to be faced with more hits than they can handle, or with “off-topic” items. For systematic reviews or other types of searches by advanced users, native databases may be more adapted, due to additional search features and a field-specific coverage. But the central index and searching capabilities in Oria must not be underestimated. Field searching proved to be quite efficient, despite different indexing standards and metadata inconsistencies from one content provider to another. Provided that one knows the limits of Oria and makes use of the available features of its advanced interface, it can turn to be a great starting point for exploratory searches.