not really true a 1080 can do 535 sol now. even if it cost you $500 it's worth it
currently 1 sol for every $1 invested is a good compromise
1080s normally run more like $600-$650.
I don't think I've EVER seen one with a price tag under $589 as new cards (that is lowest current SALE price on Newegg).
They also have a MSI RX 470 on sale at $169 (as well as the Sapphire blower-style cards like the ones I bought and I think one other card by someone else) - not sure it it's Phil's favorite version or not offhand, but it looks like a no-backplate design.
yeah i know that they are sold at $500, but still at 589 with 535 sol they are not that bad, keep in mind that the miner is not finally optimized yet
as logn as you have 1/1 ratio between hash and $, it's good for me