One company's solution can be another company's nightmare, especially in component packaging. A desire to maximize functionality and fit space constraints can result in something like this monster (25mm x 50mm) package on package (PoP). While likely satisfying a market need, this component will be challenging from a manufacturability and reliability perspective. For example, the package weight will likely reduce solder ball height to less than half the diameter, increasing the likelihood of pad cratering and thermo-mechanical fatigue. If you are looking for real solutions to PoP challenges, contact Craig Hillman, firstname.lastname@example.org.