Here’s paper which has pretty nice comparison of QuadTrees and R Trees:
Quadtree and R-tree Indexes in Oracle Spatial: A Comparison using GIS Data
Some differences:
- Quadtrees require fine-tuning by choosing appropriate tiling level in order to optimize performance. No specific tuning is required for R-Trees.
- Quadtree can be implemented on top of existing B-tree. R-Tree -cannot
- Quadtree indexes are created faster than R-tree.
- R-trees are much faster than Quadtree for nearest neighbours queries.
- R-trees are substantially faster than Quadtree for window queries, like “inside”, “contains”, “covers” etc.