The eastern boundary between DRC and Rwanda and Burundi follows the course of the river which flows from Lake Kivu southwards into Lake Tanganyika. Your boundary between DRC and Burundi correctly follows this river, but the boundary with Rwanda is generalised and normally too far west. The boundary in the GAUL dataset is better in this respect.
Comments
boundaries between DRC and Rwanda/Burundi
The eastern boundary between DRC and Rwanda and Burundi follows the course of the river which flows from Lake Kivu southwards into Lake Tanganyika. Your boundary between DRC and Burundi correctly follows this river, but the boundary with Rwanda is generalised and normally too far west. The boundary in the GAUL dataset is better in this respect.
Internal admin boundaries in DRC are very good