Why ?Only advantage of SP over G is the memocard and LTE.
If you can live without them get MotoG/16GB and you'll be OK.
I changed from Moto G to SP, but regret it...
I think SP is better compared to the Moto G in everything except the price !
I'll be getting the ZR if Sony won't price the G right but I wonder how long Sony push out updates for the ZR coz its getting old !If possible try to save enough money for Xperia ZR or LG Optimus G. Since both the product are getting pretty old, you may have huge discounts on them.