...Well I don't know if you've looked up the profits that the Antminer L3+ ....
And why would I look up the profits of an X11 miner for a thread about a SHA-256 miner? 
...So you're saying that as soon as you have your mining equipment payed off (you hit ROI) ....
No one that knows what ROI stands for (Return On Investment) has ever said that.