How is the quality of Dongbao mattress? Is it safe and durable?

I have been an old customer of Dongbao for 6 years, almost 7 years. I am satisfied with their bedding, bedstead and mattress. After sleeping for so many years, the quality is still so good. There has never been any collapse or broken bedstead. I also learned about their products. The materials used are environmentally friendly and have no harm to people's health. This is really safe to buy.