brifly on your off topic.
The 520 is a great device; has a micro sd slot, about the same size as an idevice, and excellent value.
Wade, don't make the mistake of comparing hardware specs for devices with different OS's..... you can't. And the Moto G isn't a fair compare to 520 due to screen sizes etc.
Either are great choices for folk for whom it wont be their last device. Personally for my small people, I didnt spend more than I could, on a suitable device, because I knew I'd be buying another one sometime.
The 520 was my first thought but it lacks a front camera so no video skyping etc plus it's 512mb ram gives it a limited life in the world of wp8.
Another aspect to consider is the Moto G has unofficially been recognised as being fairly watertight which is a bonus
Are you saying you want your 8 year old child to have a smartphone with a front facing camera?