It has to do alot with the maker of the furniture, not all cushions are created alike. Having said that, the cushion is generally slightly softer in "ride" when there is springs inside, like a marshall coil cushion. Springs will always hold the shape of the foam better over time than foam alone, one reason is the springs are pushing the foam back to its original shape. This occurs because the foam is sandwiched around the springs.

The seat deck below also plays a part here, on whether the cushion will last. A good spring deck ie: 8 way hand tied or drop in coil,will make the cushions last longer absorbing some of the weight of user over time.

shoppes1, thank you for the explanation.

My sofa will have the 8-way hand knotted spring deck. It's a Stickley sofa. I just worry that the spring-down cushions may be too soft for me and it will contribute to my lower back pain.

These spring-down cushions did feel more comfortable than the standard cushions in the store, though. I have the standard cushions on my sofa at home, and they have flattened out and are not comfortable to sit on, so I hate them. I'm keeping my fingers crossed that the spring-down cushions will work out for me. Stickley offers an extra firm version of their standard foam cushion (no springs), but they didn't have one of those cushions to try out in the store, so I passed on that type of cushion.

Mia, my Sherrill sofa is 6 mos old and it gets compressed areas that do not decompress. It happens every time I lay down on it. They have switched out the cushions 3 times, but same problem occurs. $3,300. I am told the local family owned store has never seen this before. Did your problem get resolved?