Pretty sure he asked about a 2 door fridge, not two 1 door fridges. Also, pretty certain the KK SD uses Dixell controllers, is rated to 43 ambient temp, and actually publishes their power consumption on their site (260w) where as the series X just states it's '10% more efficient', related to what? The series 4? Pretty sure two fridges, with two compressors would draw a fair bit of power, whether or not that's less than a single GD or SD who knows. I'm not saying that you have a habit of lying about most of the things you claim, but you lie about most of the things you claim. Including your fake reviews that are still up.
As far as the SD is concerned it states 260w which works out to about $2 - $2.50 per day running full time 24hrs a day. It's probably going to be a fair bit less than that, which is not really a huge cost. About $600 a year in electricity if it's running 24hrs a day. As we know they cycle on and off, so expect less than that. What 2 fridges will cost to run, not sure. Don't see how 2x compressors running would be more efficient than 1x compressor but not sure.
Also, not sure what 'more mechanical parts' means in relation to the GD. I would think two fridges with two compressors would be more of a risk that one shits itself over a single unit but who knows.
As for buying two fridges, it would be around $640 per fridge for the series X, which makes it about $1280, as opposed to $1400 for the GD and $1600 for the SD so it's not really that much of a saving.