The Samsung 9100 Pro 4TB is the objective winner of this comparison, securing victories in five out of seven measured specifications. Its most significant advantage is its storage capacity, which is 100% greater than that of the alternative. By offering double the space of the Samsung 990 Pro 2TB, it provides a substantial upgrade for users requiring extensive room for their data and applications.

Choose the Samsung 9100 Pro 4TB if your primary requirement is maximum storage volume for large-scale projects or extensive media libraries. Conversely, the Samsung 990 Pro 2TB is the better option for budget-conscious users, as it holds a 65% advantage in MSRP. Selecting the latter allows you to prioritize cost efficiency while still benefiting from the specific performance metrics where it outperformed the larger model.