Plusthinking Iq :
its not all about the fps, and you need a amd 280 to notice a fps improvement over the 750ti.
So the difference between an 260x and an 750ti is big enough, but the difference between an 750ti and 270x is unnoticable?
the improvement of an 750ti over the 260x is lower than the improvement from an 750ti to an 270 ....
all in all if his psu has the needed connectors he is better of with the 260x on an limited budged.