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As I have to go off the published fees for all the services, Genesis looks to be almost 3x the upfront cost of Giga and HashFlare at 2x the cost. That immediately means that a longer time to recover cost before profit. Not insanely huge, but enough to cause me pause. (I used Ethereum mining for comparison as it is currently available on all three platforms)

If we also factor in that both those services are contracts with a defined end date (2 year and 1 year, respectively). While you could argue that a hardware refresh every year or two is necessary, I would rather be able to get additional life out of a mining rig that is dedicated to me with no expiration date.

With those two factors considered, Giga Watt appears to offer a more profitable platform, due in part to their delivery model.