Guys, both of you are having issues with math, or you're not aware of dual mining. Here's how it goes for me atm: Eth $28,43, Monero $30,22 and Dual Eth+XVG $34. This is real Eth+Xvg profit, not the one estimated by WTM on the number of coins you're "supposed" to get (which would be $37).
You're welcome =)
P.S: not sure why would someone use this solo miner at all, when dual is always more profitable, even with higher fees.
You have issues with the math. 25ish cards should earn you this profit daily, so if you factor the 0.5% devfee, the increased power draw of 40 watts per card, add the additional stress on the GPU, cooling, PSU, fans, heat output, air conditioning - you are basically running at a very slim margin.
When I say "in my case", it means I measured everything, with wattmeter, including power loss in cables. I don't count asset depreciation since my rigs have made 3+ fold profit already. Calculations above actually use same power draw for Eth and Eth+xvg. For Eth solo it should be less, as you noted, but its not much difference in $, since my electricity costs around 3 cents US and I don't use aircon, because its 0 degrees outside temperature =). Hope this clears things up.