The Samsung 9100 Pro 8TB is the objective winner of this comparison, securing victory in five out of seven measured specifications. Its most significant performance advantage is its sequential write speed, which is 113% faster than that of the alternative. By outperforming the Samsung 990 EVO Plus 4TB across the majority of technical categories, the 9100 Pro 8TB establishes itself as the superior option for users prioritizing raw hardware capabilities and high-capacity storage performance.

Users who require maximum write speeds and the largest available capacity should choose the Samsung 9100 Pro 8TB for their high-performance workloads. Conversely, the Samsung 990 EVO Plus 4TB is the better selection for budget-conscious buyers, as it offers a 67% advantage in MSRP. Selecting between these two drives depends on whether the user prioritizes the significant sequential write improvements of the larger drive or the cost efficiency provided by the smaller model.