For those debating price, this is what Gibbo posted.
Quote taken from this thread.
RX 580 has been reduced to allow it to fit into the pricing stack, this is why 580's are now appearing at £199 and to be honest that makes the RX 580 better value.
I believe 580 8G will stabilise around £219 after promotion period and 580 4G will drop in at £199, so 580 8G at £199 is a steal.
Expect to 590 sitting at £250 - £350
Quote taken from this thread.