Nexus4 costs only 250$.
HTC One looks best.
Iphone is cool but expensive as fuck.
Samsung S4 is fastest on paper but slow as fuck in reality.
Lumia 1020 is very, very fast an has best camera in the market BY FAR.
You're severely mistaken if you compare phones just by technical specs. They have different operating systems. Nexus4 is slower on paper than S4 but vanilla, clean Android makes it far more reliable, stable and faster. Iphone5 is on paper slower than anything but in practice it is damn fast. Same goes for nokia.
If you're on a budget or don't feel like spending fortune on phone then nexus4.
If you like apple then iphone5.
If you don't need many fancy apps and use phone primarily for maps, calls, camera and other basic stuff then Lumia is best by far.
Biggest disadvantage of lumias is being tied up to the carrier. You just won't buy unlocked new lumias.