The Western Digital WD Black SN850X 4TB is the objective winner of this comparison, securing five out of seven total specification categories. Its most significant advantage over the competition is its storage capacity, which is 100% better than the alternative. While the Western Digital WD Black SN770 2TB holds a 74% advantage in MSRP, the superior capacity and broader spec-win count establish the SN850X as the more robust hardware option for high-performance storage needs.

Users who prioritize maximum data storage space should choose the Western Digital WD Black SN850X 4TB to take advantage of its doubled capacity. Conversely, the Western Digital WD Black SN770 2TB is the appropriate selection for buyers who are primarily focused on the MSRP advantage. By weighing the importance of total storage volume against the initial cost, users can determine which of these two drives best aligns with their specific build requirements.