Rx480 or Rx470 plz

Hi first i will appreciate any help guys ..
I am looking for some help on Rx 480 & Rx 470 cards
I want to build 3 rigs but i am confused about witch cards to buy ..
any advice ?

to make it easy,
I can buy these cards in my country

1- Sapphire Radeon™ RX 480 8G D5
2- Sapphire Radeon™ RX 480 4G D5
3- SAPPHIRE NITRO+ Radeon™ RX 480 8G GDDR5 OC
4- SAPPHIRE NITRO+ Radeon™ RX 480 4G GDDR5
5- SAPPHIRE NITRO+ Radeon™ RX 470 8G D5
6- SAPPHIRE NITRO+ Radeon™ RX 470 4G D5
7- SAPPHIRE Radeon™ RX 470 4G D5

witch one is the best for hashrate and watt please

Thanks in advance,
Regards,