If you want to buy lipumia 520 you should go for ir cuz its the most durable , reliable and user friendly phone . talking about the speed it gives zero lagging its responds real fast and gaming experience is overall good no heating on high fps games it works really good windows phone has contra which is really helpful at many a times . its literally an undistructable device it fell from my hands many a times and still it looks as it is in mint condition and the screen is still safe . I sropped it in water still it is working as its in mint condition its display is very vibrant and its a good thing