Hint: they won’t last, inherently defective.
Many re-sellers will tell you that the attached pillow-top, single sided mattress is ‘new technology’. This is part of their sales pitch, using ‘buzz words’ like new technology.
Ultimately, there mattresses are inherently defective and designed to fail necessitating early replacement.
An attached pillow-top can look plush in-store but after a few months (yes, months!), years at best, when the pillow-top section fails the whole mattress needs replacing.
With the comfort and support sections being one unit, the whole mattress fails due to body impressions forming in the comfort foam layers.