I know what you guys mean with the price of the device but it should last about 10 years according to the manufacturer.
If it last that long it should cost between 350 - 400 USD per year.
So if it save you 33 USD per month, it is worth it.

It's just an idea, I'm not planning to do that. Mining is not profitable since a long time.
Only Chinese are mining because they have the cheapest electricity.
I was just wondering how to get cheaper power or more efficient mining.