I've just moved from a LG 34UM95 (IPS) to a Dell S2719DGF. I mainly game, and the Dell is vastly superior. The color reproduction doesn't "seem" as nice when I have them side to side, but when turn off the LG, the DELL looks great. I know a lot of TN screens are rubbish, but this one seems the pick of the bunch.
My 'problem' is that I recently bought a 1080Ti and want to use it to its full potential which I currently cannot with my Dell U2715H (60Hz IPS) but I'm very worried that the Dell S2719DGF will look poor in comparison side by side.
Run them side by side? Best of both worlds.