I don’t know about you, but I can feel and see lag/unresponsiveness, when the FPS are less than my monitor’s Hz. In games, you always want more FPS than your Hz, to have zero game lag, and eliminate screen tearing due to low frames. There is a huge thread about people arguing over “what the eye can see” and such, in the UT forums, if you’re interested. I’m not. 
I definitely prefer it here in the Engine forums over the UT forums, as people are much more mature. Also, I’m not an Unreal Engine fanboy, as I suspect there are many of(without solid cause & comparison testing)…I’ll use the tools that live up to my standards.
Just to note, Unity uses about 0% CPU, and about 250MB RAM. :D:D:cool: