First, we have furnished an entire house with Wayfair mattresses. That is a king bed, two queen beds, and four twin bunk beds. The mattresses have been fantastic. We have purchased all firms so I can only speak to those, but they are comfortable, affordable, and overall good value. We purchased the most recent mattress for my son’s new loft bed (also from Wayfair). We went with the firm, 6 inch to keep his head from hitting the ceiling. As the reviews stated, the mattress in its full expansion is probably closer to 4 inches, but for a 70 pound 10-year-old, it was perfect.