Most of those finishers are basically liquid sugars for the plant to intake, theres nothing wrong with adding them but they will need to be flushed out or you can get funky tastes etc with them. If you want an all natural sugar that will both sweeten buds and dense buds you can always add like 2-3 tablespoons of molasses in the last several weeks. Not only is it available at nearly every grocery, it doesnt require flushing the way a synthetic "bud candy" would.
Try what makes you happy, and you'll at least learn what works for you and what doesn't. Happy and healthy growing.