Well, there are top players playing at 40 FPS on a 60 hz monitor while maintaining top level, and there are people using 144 Hz monitors that are on the very bottom skill wise. Online latency and reaction times are what set the good players apart from the bad players... It's preference really, 144 Hz, provided you can push 80-100 FPS at least, is going to look really smooth, and what's known as ghosting will be completely gone. In LoL you may not have the biggest advantage with a 144 Hz display, though teamfights and quick camera movement will all appear super sharp, no blur. However, how much does it really matter... IPS is definitely the way to go over TN, no question, no argument, no comparisons - two different types of tech.