If you are using a spriteNode, I would use .setScale, or .xScale or .yScale , because those are specifically for sprites. .size can also be used for the size of labels, and text views in UIKit.
Lets say you want the sprite to be 2x bigger:
theNode.xScale = 2.0
theNode.yScale = 2.0
Note that they have to be floats, not Integers
So to sum it up, .setScale is for spriteNodes and images in general, and .size is for a vast amount of things that aren't images, like labels and more. So if you are using a sprite, use .setScale. If you are resizing a block use .size.
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