I've spent hours doing this vs that maths so it's clear to me, opt for the miners, if you rent for one year that's all you get, plus it's trusted to a third party.
Owning the rigs offers a more secure investment as you can keep on mining until they die, or you sell them after a year, up to you. In the long term, owning your own rigs works out better. Plus you can look at them whenever you want, can't do that with rentals
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