Like sleeping on a partially deflated air mattress!
I was very disappointed with the Hilson Deep Open Coil Mattress. I expected a mid-quality mattress that was medium-firm. The Hilson mattress was very squishy (like a partially deflated air mattress). The mattress arrived wrapped and vacuume-sealed. Unfortunately, it felt as though the Hilson mattress never completely expanded. 

While I was very unsatisfied with the product, I was very pleased with Wayfair's customer service. Wayfair really did everything they could to make the situation right. I am very thankful for the quick resolution.