Hi shan808,
Your comforters would be different from the mattress pads that you linked which would have a denser polyester fill than the comforters and would also have a tighter quilting pattern and would be more resilient than the comforters but your experience certainly increases the likelihood that either one of them would make a good choice (although I would still make sure that there is a good return option just in case it’s not).
You can’t “feel” the quality of the materials in a mattress because lower quality/density and less durable memory foam can feel the same or very similar to higher quality and more durable memory foam depending on it’s formulation … it just doesn’t last as long before the foam softens or breaks down and loses the comfort and/or support which was the reason you purchased it in the first place. Lower quality materials can be just as firm or soft or just as supportive and comfortable as higher quality materials … they just won’t maintain their comfort and/or support for as long. There is more about the different properties that can be chemically formulated into the many different types of memory foam (regardless of density) in post #9 here and there is also more about the many variables that can affect the durability and useful life of a mattress relative to each person in post #4 here.
Phoenix