Assuming that the payouts remain fairly constant over the next few years
It won't. With difficulty increases your payouts will drop 15-20% every 2 weeks.
Just like CEX the only way to make profit off these shares is through day trading.
They lose value fast and currently are not even close to a rate at which holding would be profitable.
According to Crypstsy, the original principal will be made back through dividends in a year or less. That's 100% ROI in a year. Stocks don't have anything even close to that type of ROI.
The difference, like you said is that these will eventually depreciate in value. Which is why there needs to be diversification. At set intervals, reinvest some of the dividend payouts into newer vehicles. MN3, MN4 eventually when they come out.
Also...these shares have gone down from .180 to .100 back up to roughly .150. That means as of today, I've lost .030BTC off the principal, or about 16%. According to my very rough calculations, I'll make up that 16% loss in 7-8 weeks if it stays at that price, and will be even despite the loss to principal.
I actually think there is some long term money to be made here without day trading. I'm just trying to wrap my head around it.