Why would anyone buy a 520 when full speced phones are available on android for slightly more (even though they are from Indian Manufacturers but have good reviews and satisfied owners)? The realities of Indian market are vastly different from US and Nokia / Apple don't give themselves a fair chance to penetrate in the middle / upper middle class segments where Samsung / Sony have a strong hold now because of their (Nokia/Apple) apathy.
Those full "specked" phones have a couple of issues
1. The screens are horrible bad colors and contrast
2. Android with no hardware optimization. Runs like crap.
Bonus 3. Horrible horrible horrible cameras.
So sure, they're fully specked, but... Not really. I'd take a 520 or 625 over any cheap full specked android or mid range android device. And I'd take a. 925 or 1020 over any high end android.