I just upgraded my test environment to 700b2 last week, was 607b. I can tell you the upgrade went way better than past ones. We are also heavily customized when it comes to forms and reports, some BPMs, BAMs, etc. There were only 2 forms that failed the upgrade - customer entry and tracker. I have those lovely warnings with orphaned controls which generally mean you're better off starting the customization from scratch again. We don't have anyone in testing yet so there could be other unidentified issues to come. Let me know how it goes for you!
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