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The plugin works exactly as described and you SHOULD AVOID IT. It loads the images for each variant on the initial page load, this means every image gets loaded. So your page size will be the size of every image variant regardless of if the customer selects an option or not.
If you're like me and were planning on using different images for size and color variants then you will end up with a page 10mb in size that loads very slow. Also because of the speed you will run into issues on the initial page load with other odd images showing. The only solution I found was to switch to lemonstand.