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 latter drive delivers a 103% improvement in sequential write speeds, making it the superior choice for tasks that rely heavily on rapid data writing capabilities.

Users who prioritize maximum sequential write performance for demanding workloads should choose the Western Digital WD Black SN8100 4TB to take advantage of its substantial speed lead. Conversely, the Samsung 990 Pro 4TB is the better option for budget-conscious buyers who prefer the 37% MSRP advantage over the raw write performance of the alternative. Selecting between these two drives depends entirely on whether your primary requirement is cost savings or high-speed data writing.