Advice building a multi-algo miner with RX 470 / RX 570

Hello,
I need advice for a new miner. I want to buy 6 RX 470 or 6 RX 570 .
My options are:

MSI Radeon RX 570 Armor OC 4GB -> price 939 RON ( 1 $ = 4.17 RON)
GIGABYTE Radeon RX 570 GAMING 4GB -> price 934 RON
Gigabyte Radeon RX 470 G1 Gaming 4GB -> price 874 RON
Asus Radeon RX 470 Strix 4GB -> price 900 RON

I would like to make a decision based on the mining flexibility so when equihash mining isn't profitable to be able to switch easily to another algo like Scrypt , X11 and so on ..This means that the card should be easily modded and stable.
Based on your experience, please suggest what should i pick from the above list or what else to take into consideration.