Is the Nisien Hybrid good for side sleepers?

The gel memory foam top layer cushions shoulders and hips, and the medium feel generally works for side sleepers of average weight. Heavier side sleepers may want more pressure relief than it gives.

The coil core allows more airflow than an all-foam bed, and owners generally report it sleeps cooler than foam mattresses. The foam top layer still retains some heat.

How firm is the medium feel?

It sits in the middle: soft enough to sink into slightly at the shoulders and hips, firm enough to keep the spine supported. Back and combination sleepers tend to like it.

Do I need deep-pocket sheets?

Yes. At 14 inches thick, standard sheets may pull off the corners, so look for deep-pocket sets rated for mattresses of that depth.

Does it work on an adjustable base?

Pocketed-coil hybrids are generally flexible enough for adjustable bases, but check the base's weight limit, since this mattress is heavy.

How does it compare with an all-foam mattress?

It offers more bounce and airflow than all-foam, with coils adding support under the foam. All-foam beds isolate motion better and are usually lighter.