The Western Digital WD Black SN850X 4TB is the objective winner of this comparison, securing more individual specification victories than its counterpart. While both drives share identical performance characteristics across most metrics, the 4TB model provides the most significant advantage by offering 100% more storage capacity than the 2TB version. This doubling of available space makes it the superior choice for users requiring maximum data density within a single drive slot.

The Western Digital WD Black SN850X 2TB is the recommended option for budget-conscious buyers, as it holds a 63% advantage in MSRP. This model is ideal for those who prioritize lower initial costs while maintaining the core performance features of the series. Conversely, the 4TB variant is the necessary selection for power users and enthusiasts who need the expanded capacity to house large libraries of files and applications without compromise.