The be quiet! Dark Base Pro 901 is the objective winner of this comparison, securing victory in five out of eight evaluated categories. Its most significant technical advantage is the inclusion of additional 2.5" drive bays, which offer 67% more storage capacity than the alternative. This superior configuration makes it the more versatile option for users requiring extensive internal hardware support and a higher volume of storage mounting points within their system build.

The Phanteks XT Pro Ultra is the ideal choice for budget-conscious builders, as it holds a 37% advantage in MSRP. Users who prioritize cost-efficiency over maximum storage capacity will find this model more suitable for their needs. Conversely, those who require the expanded drive support provided by the be quiet! Dark Base Pro 901 should select it to ensure their storage requirements are fully met despite the higher cost.