This site states this specific claim directly in its stack comparison: clear 60-day guarantee terms, stated upfront.
This site pairs this claim against "often unclear on what's actually inside" as a stated weakness of a complicated stack — worth noting this claim is about guarantee clarity specifically, not about ingredient-panel clarity, which this site separately admits is incomplete.
Worth reading this claim narrowly — this site is direct elsewhere that individual ingredient amounts are not disclosed, so "clear terms" here refers specifically to the guarantee, not to full formula transparency.