Ikea is a European brand that started its business in Sweden. They mostly sell home products and furniture, but do sell a number of different mattresses. Their Pricing is very competitive and as such you can generally find a pretty good IKEA mattress from anywhere around $200-500 for their spring or foam models and $350-900 for their latex models.
IKEA mattresses are fairly standard in comparison to the other brand name mattresses, but they really gain an advantage with their pricing. The mattresses have minimal off gassing and do not typically have the problem of “sleeping hot”. IKEA beds come with a 20 year warranty, which is great, but don’t expect to have your mattress last the entire length of the warranty anyway.
A trend with IKEA mattresses is to rely on the mattress pad for the necessary cushion and plushness. This can be a good or bad thing depending on whether you like the idea of a bed top. The foam models of IKEA adhere to the same problems as most foam model brands elsewhere. After a few years, probably no more than 5, the foam will begin to lose its rebounding feature and become stuck in your sleeping groove. This creates the problem of no lower-back support and ultimately can give you an unpleasant night.
The firmer IKEA mattresses do not have as much as a problem as the softer ones (less foam), which makes the firmer mattress a better choice in the long term. You can always use a bed topper to up the cushion factor on a firmer mattress as well so you can have a longer lasting mattress. There has been criticism with the firmer mattresses too however, noting that they tend to be very bouncy and can be a problem if your spouse tosses and turns.
If you’re looking for quick and cheap fix for a bed than IKEA might be a good idea for you, but if you’re needing a longer lasting and better quality mattress you would be better off with something else.