Is the SomosBeds Premier good for side sleepers?

Yes. The medium-firm gel memory foam cushions shoulders and hips, which suits side sleepers. Heavier side sleepers may want a softer top layer.

Does it come with a foundation or box spring?

No. The mattress is sold alone and is compatible with adjustable bases, which you buy separately.

Is it good for hot sleepers?

The gel-infused foam is meant to sleep cooler, but it is still an all-foam mattress. Some owners report it sleeps warm.

Medium. The high-density support base gives it a medium-firm feel overall.

Can I use it on an adjustable base?

Yes. It is listed as compatible with adjustable bases.

How does it compare with the Casper Original?

Both are all-foam mattresses with a medium feel. The SomosBeds Premier uses gel-infused memory foam over a high-density base, while the Casper Original combines polyfoam and memory foam with a zoned support core. The Premier is the simpler build; Casper has the longer track record and more owner feedback.