Differences between shapes
How do I know which shape is better for my design? What benefit does an EE have over a PQ for example?
EE shapes are typically the cheapest compared to other shapes because they are easily manufactured.
Regarding the question which is better, it depend on what you are looking for. PQ shapes has a round center leg which enhances the winding coupling, and also have a larger core surface area that allows them to better remove heat with a heatsink attached than EE shapes.