Relational Junction for Salesforce backs up and will restore typically any Salesforce object that is allowed by the Salesforce API and security rules. You cannot create certain objects in Salesforce, such as AccountHistory, because it’s just not allowed by the Salesforce application. There are no issues with handling binary data, such as Attachments an Documents and ContentVersion.
It would be easier to tell you what Relational Junction for Salesforce doesn’t copy. This is a list of current objects that cannot be backed up because they are not “real” objects or have specific technical limitations of the API in copying records without some sort of specific qualifier.
ActivityHistory AggregateResult AssetTokenEvent AttachedContentDocument CollaborationGroupRecord CombinedAttachment ContentDocumentLink ContentFolderItem ContentFolderMember DashBoardComponent DataStatistics DatacloudAddress DatacloudCompany DatacloudContact DatacloudDandBCompany EmailStatus EntityParticle FeedLike FeedTrackedChange FieldDefinition FlexQueueItem FolderedContentDocument IdeaComment ListViewChartInstance LookedUpFromActivity Name NoteAndAttachment OpenActivity OwnedContentDocument OwnerChangeOptionInfo PicklistValueInfo PlatformAction ProcessInstanceHistory RelationshipDomain RelationshipInfo SearchLayout UserEntityAccess UserFieldAccess UserProfileFeed UserRecordAccess Vote