The Western Digital WD Black SN8100 4TB is the objective winner of this comparison, securing more individual specification victories than its competitor. While the Samsung 990 Pro 4TB holds a 37% advantage in MSRP, the Western Digital WD Black SN8100 4TB provides a significantly more impactful performance edge. Specifically, the Western Digital drive offers a 103% better sequential write speed, which stands as the most substantial technical improvement identified between these two storage solutions.

Users who prioritize maximum sequential write performance should choose the Western Digital WD Black SN8100 4TB to take advantage of its superior throughput capabilities. Conversely, the Samsung 990 Pro 4TB is the more logical selection for budget-conscious buyers who value the 37% MSRP advantage over the raw write speed offered by the alternative. Both drives share identical performance in three measured categories, making the decision dependent on whether your workflow requires faster writes or lower initial costs.