Let’s see if we can make some sense of it all, so you’ll know how to make the choice that’s right for you.
Although manufacturers use different terminology and might vary the specifics a bit, when all is said and done, there are basically three choices in cushions. The first choice is the all-foam cushion. This is usually constructed of a high-density foam core covered by a softer layer of convoluted ("egg crate") foam, and then a polyester fiber wrap, all enveloped in downproof ticking (which prevents feathers from poking through).
This is the cushion of choice if you like a very firm seat and you want the fewest possible wrinkles in the fabric.
This is what an all-foam cushion looks like in a finished sofa. Notice that there are no wrinkles at all on the seat cushions, and only a few on the back cushions. Back cushions will almost always be of slightly different construction than seat cushions, because they need to be a bit softer, but they still have to be matched to the seat cushion. A softer seat cushion requires a softer back cushion, or the body will jackknife — pitch forward when sitting. This cushion is relatively maintenance free. When you get up from sitting on it, you won’t need to do any fluffing, plumping or primping … it will look just like it did before you sat down. (I think this choice is especially good for a bachelor.)
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