Winning Combination: A Knee Pillow and a Good Mattress Posted by Eileen Pelletier on October 17, 2017. 0 Comments I travel very often, and every hotel offers a different type of mattress. Some hotel mattresses are firmer, others much less so. The hotel I stayed in last had a mattress that was like sleeping on a concrete slab. I never had a worse night's sleep. Thankfully, I brought my Sleepy Kneez pillow, which I never leave home without. My back and knees were fine after a hard night, but my shoulders are killing!