I have Heroku Connect for the Account object and I want to enable person accounts on Salesforce. Account object is supported and I didn't find any limitations in the documentation so far.
Do you have experience with Person Accounts and Heroku Connect?
This is what the docs says:
Heroku Connect supports all standard and custom objects that can be retrieved via the SOAP and Bulk APIs except for those that require the use of object specific filter criteria or are not fully supported by the Bulk API. For example KnowledgeArticleVersion and objects that end with __kav require the use of additional query criteria, PublishStatus=Online and therefore cannot currently be mapped in Heroku Connect. LeadHistory does not support Bulk Paging and the Base64 type of Attachment is unsupported by the Bulk API, and thus neither can be retrieved, once there are more than a 20,000 changed records to sync. Other exceptions and warnings may apply.
Link: https://devcenter.heroku.com/articles/heroku-connect#creating-a-mapping
Big Objects, External Objects, and Platform Event objects are not syncable.