OpenStreetMap pros and cons

Strengths

• There are no additional costs for your business - OpenStreetMap is completely free.
• Outstanding coverage.
  A large community of contributors is driving the continued expansion of cartographic data. Geographically dispersed maintainers contribute the local knowledge and "on-the-ground" details, often unavailable in official maps.
  Note: Mapbox uses OpenStreetMap as one of data sources.
• You can use alternative tilesets in clients: Wikimedia, Stamen Maps, CARTO, and others.

Weaknesses

• Being a non-profit project, OpenStreetMap does not make any commitments regarding the availability or performance.
  The service may go offline for maintenance; some functionality may change unexpectedly, making certain features unavailable; or users can get locked out without notice when executing too many data requests.
• The cartographic data may be changed by any user, which does not guarantee its accuracy and reliability.
• Some of the map details can be unexpectedly removed due to copyright infringement.
• No technical support. You have to register and update the map on your own to add details or fix inconsistencies.