Games look okay on these monitors at different resolutions. It's not ideal, but Dell has generally done a good job with the scalers in their UltraSharp monitor line. A 2560x1600 monitor can provide an amazing gaming experience. Most of my games run fine at 2560x1600 with a single Radeon HD6970
Upgrading to a 4-megapixel monitor may give you a reason to want to also upgrade to a next-generation graphics card fabricated at 28nm in the next six months.
i7-6700K, NT06-Pro, GA-Z170N-Gaming5, 32 GiB, 980Ti, SM951, 5TB HDD, Blu-ray, FTZ01, SX600-G, 3007WFP+2001FP, RK-9000BR, MX518