The team at GVM was very responsive to our needs during this project's early stages when we were still trying out different ideas/concepts before settling upon one that would work best within their system (and ours).
They helped us get everything set up correctly so it could be used easily by clients as well! I don't think there are any downsides really; they did exactly what needed doing without hesitation or complaint from me throughout my engagement here- which made working together seamless overall :).