the future of libraries in the digital age
Both DSpace and Greenstone have significantly different goals. Sometimes, it is to some extent hard to answer as if you do not know what kind of materials you have and what you will do with them. Though Greenstone is popular DL Software as better end-user usability rather than as IR and well known to our community, but for a sustainable IR, I prefer DSpace for its technical and functional capabilities. DSpace is also better for document preservation. One good thing, Greenstone has the capability of distribution on removable media. You should also think about the integration of your IR with your existing LMS if you want to do federation. Actually both are good but the adoption is also depending on technical ability from your side.
Though older, you may find the link of one of my articles
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