Master Data Services Capacity guidelines

Master Data Services was designed to work with data that is relatively slowly changing. Data that is involved in a high volume of transactions (that in some cases are stored in fact tables) should not be stored in MDS.
From a performance perspective, MDS will likely not process more than 50K distinct changes per day per model. By distinct is meant a separate call (either to entity-base staging or the WCF API). If significant changes are required, it is recommend that you perform them in batches either through entity-based staging or the WCF APIs. Both interfaces are tuned for batch operations and will generate much better performance than performing each change separately.
If you need to perform more than 50K calls per day per model, then it is recommended that you perform a proof of concept on the designated hardware.