With the primer it is quite obvious, as the bottle and the product are transparent. I suspect in my set there might be one or two other colors that are not completely full, but I can't confirm that.
You can try tapping and setting the tubes upright and wait about a day or two for the product to settle downward. You'll either see how much it's filled up (may not be evident in highly pigmented colors), or you can do a "squeeze" test to see how much squeeze each tube needs to get product out. I had ordered the other mini set as soon as it released, and *all* 4 tubes were nearly half "empty". But all had the exact same level of product, which makes me think the amount is correct as listed but with a misleading packaging.
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