XFX RX 470 4 gb – Ravencoin mining hashrate?

Hey Ravens! I am wondering what is the hash rate of a rx 470 4 gb XFX GPU?
Is it worth buying it for cheap? A good friend of mine is selling a 5 rx 470 rig for only 500 usd, crazy.
I am testing it soon so I am wondering what is the hashrate, and also which miner and mining pool should I use? Is it even worth buying this rig?

Cheers to all!