The be quiet! Dark Base Pro 901 is the objective winner, securing victories in seven out of eight comparable specifications. Its most significant advantage over the competition is its storage capacity, offering 150% more 2.5" bays for hardware configuration. While the Corsair 4000D Airflow falls behind in total spec count, it maintains a distinct advantage in affordability, with an MSRP that is 61% better than the alternative.

Users requiring extensive storage expansion should choose the be quiet! Dark Base Pro 901 to leverage its superior bay count. Conversely, the Corsair 4000D Airflow is the logical selection for budget-conscious builders who prioritize a lower initial cost over the additional features and storage capacity found in the more expensive option. Each case serves a different priority, balancing high-end hardware support against overall investment requirements.