I am considering going scratch on all of my cakes. I noticed on King Arthur's website that a cake enhancer can make a cake more moist, have a more tender crumb, and possibly make the cake stay fresher longer. WEll I am especially sold on the cake staying fresher longer-this is what I am looking for.

I am wondering has anyone used this product before and what was your pros and cons of using it? On their website some individuals mentioned it changes the taste of the cake a little? Has this happen to anyone? If so, does the cake turn out more bland, or etc.? Please let me know. I am wanting to purchase some cake enhancer if it is worth it.
Also, if someone can recommend a good versatile scratch white cake recipe with a good crumb that stays fresh longer than a day or so, that would be great as well! TIA