Nokia Lumia 520 a good phone for general purposes.Windows phone is 2 times faster than androids. Because windows are windows.
They are different from Android. In Lumia 520 its ram is 512mb but they can run asphalt 8 without any issue. The gaming performance is high of every windows phone.
But the apps level means ( no of apps) are no so much in windows phone like mouth shut app is not built for windows phone.