When I first got this replacement, it was great, and now, for the last four months I’ve been dealing with a sink hole and is killing my lower back.

The mattress is super firm and comfortable. I am happy. I recommend for people who have joint bone problems and especially the back

I have a lot of health issues with my back and haven’t been able to find a mattress that is comfortable until now. Thank you so much.

So far so good. Went from queen to king. Plenty of room now for the 2 of us. Seems to be doing it's job.

This mattress starts out firm at first but after a few nights sleep is very comfortable. I normally sleep on my back and it’s very supportive of them mid to low back and cradled your body!

Very firm but comfortably supports my spine after two surgeries. I go right to sleep without tossing and turning like I did with my previous mattress.

Once I lay down to sleep, I fall to sleep immediately and sleep the entire night. It is very comfortable and no aches or pains. I am totally happy and satisfied with it

Having slept on our new Serta Perfect Sleeper X Hybrid Knox Plush Cal King for two nights has been wonderful. Supportive and comfortable for much needed good night sleep.

I’m a side sleeper and was looking for a firm mattress that would not make the pressure points in my shoulder and hips hurt. This hybrid mattress has been perfect for me!

Perfect balance of plush with firm that fits both of us!