My platform has licensed a part of Brightlocal search rank tracking for multiple years and they've always been reliable. Easy to work with too. We do not use them for citation management (have our own).
While I've no direct working experience with Whitespark, I've always seen them as knowledgeable on our space and benefitted from some of their thought-leadership.
Both are worth an intro/demo call to learn more IMO.
@dave101 if you've got any questions in particular about BrightLocal citation building, please feel free to pop me a message and I'll try to answer those for you. As Eoghan mentioned, demo calls can be really helpful to get an understanding of how we can meet your needs. You can book one in here if that's of interest.
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