No one uses 1080 Ti for ETH mining, that's not what these cards excel at. It's just ETH is the largest alt coin, and because of that it became some kind of universal "mining benchmark" (mostly for sites/channels where people know very little about mining). Nvidia cards with gddr5x memory (gtx 1080, 1080 ti, titan xp) are not competitive in ETH mining, they're good with other algos, so when you try to figure out profitability you don't compare something like 295x2 mining ETH to gtx 1080 ti mining ETH, you compare it to 1080 ti mining whatever it is the most profitable for nvidia cards at the moment. Which might be equihash, or Lyra2REv2, or skunkhash, or a dozen other algos.

And I'm not even sure that ETH is the most profitable algo for 295x2 cards, right now they're probably doing better on cryptonight.

295x2 almost similar to 2 x 290x, 290x produced with 44 chips and each gpu on 295x2 also have 44 chips, 88 in total. Referring to this https://www.nicehash.com/profitability-calculator/amd-r9-290x?e=0.1¤cy=USD , most profitable algorithm for 295x2 is Crytonight and second ones are Equihas.

Since 295x2 is dual-GPU card, so 2 (295x2) equal with 4 cards. if you are using default setting(without OC), you'll get around 28.xx MHs each GPU or 57-57.xx in 1 (295x2) or 114-115 MHs for 2 (295x2). am using 1 (295x2) equal with 2 cards, each GPU get 30-32 MHs (OC mode) so I have 60-64 MHs.

By keeping it as cool as possible and powering it with a high-quality PSU. If you do it right, it'll live happily for many years. There's plenty of general mining guides out there, including on this forum, just start reading. GPU mining is not a "one button press" thing, you'll have to do some research about undervolting, setting clocks, fans etc.

Come on, just read the previous post. 295x2 is faster for both xmr and eth. But even if you don't care about the power usage, this is still an old card, they haven't been produced for quite a while now so you're likely buying it used. You also didn't say anything about prices. If it's 1080 ti for $800 vs amd 295x2 for $10000, then no, go with nvidia. The amd card has been out of stock for a long time now, so we've no idea what you are to pay for it.

For the two coins you named the AMD 295x2 wins hands-down. Almost two times higher hashrate than the 1080 Ti. But it's an old power-hungry card, so I wouldn't buy it unless you're getting a very good deal.

You will get it for 120$ around when you will use referral code in wagecan.
I am also thinking of ordering one as it is quite hard here to exchange bitcoin for local fiat right now because of government's bullshit decisions and no any other cards work here in my country.

Yes price of wagecan card is quite high but they are taking benefit of being the only one choice for non-eu customers.

I have used Wirexapp for that matter, but any Visa card should do the trick. I believe there was a law in like 26th May or something regarding Money laundering, so now the limits are much lower for unverified accounts (100$) and If you want anything higher, you will need to provide more info. If the amount in your PayPal account is spendable, I suggest selling it for BTC and then selling your bitcoins to a payment method that you actually have (Bank transfer for example).

We got a list here: https://bitcointalk.org/index.php?topic=1242788.0 I suggest going with UQUID or CoinsBank as I have used them before, I'm however unsure about the ability of ordering these cards without providing Residence proof as I was using virtual card with low limits and I didn't need to do any of that. You just must understand that in order to withdraw any funds, the card must be a Visa and not a MasterCard.

Visit https://whattomine.com and do a comparison yourself  

I agreed, with current coin price and difficulty, you can't earn 2k dollars per month with only 1 mining rig at max of 6gpu. You need at least 4 to 5 mining rigs to achieve your goal.