Even with a rig like that it will take around 10 months to break even. Ethereum will be moving to proof of stake in the future. There is no set date but it could be in approximately 1 year. At that point all these gpu rigs will need to switch to other less profitable cryptocurrencies.
We're reaching the point where it may not be possible to break even before Ethereum switches to proof of stake. Consequently, it's recently become easier and cheaper to buy gpus suited to mining.
I did say "if you already have a rig". For the time being, it still makes more sense to mine than liquidate cards.
The market is all over the place right now for mining altcoins. NiceHash-Cryptonight (pays out in BTC) will currently gross ~$18-20 a day with the same mentioned setup.
We're reaching the point where it may not be possible to break even before Ethereum switches to proof of stake. Consequently, it's recently become easier and cheaper to buy gpus suited to mining.