It's easy to set up, it works well for our needs (tracking sales leads), has no issues in reporting or data export/import which are common problems I've seen elsewhere at other integrations of this nature; however we do have some minor quirks here & there but nothing major so far! We're using GAC as part of my role within Salesforce Marketing Cloud - tracking lead activity across all campaigns into one place helps me understand how each campaign performs compared against others etc.; also allows us to see what content / assets perform best when creating new opportunities from existing contacts e.g., emails vs website visits versus social media impressions.