Below, we'll go through our top 5 favorite firm mattress toppers. Best Organic: Avocado Vegan Mattress Topper. If you prefer an eco-friendlier mattress topper, we … These toppers are a great way to improve the way you sleep and help you to use an old mattress for more years without buying a new mattress. Mattress Topper Selection. Airweave is a recent addition to the mattress world, with their revolutionary airfiber material that is made of the same polyethylene that is in fishing line, but is weaved together into an ultra-durable, firm construction. The best firm mattress toppers are in great demand and there are a number of reasons why they are gaining popularity. Here is a breakdown of Airweave's Top Mattress:. This latex mattress topper has a firmness rating of 44 ILD (latex density), making it an extremely firm choice and one that beats out most memory foam options in … Best mattress topper and best memory ... Side sleepers and anyone who suffers from back pain should consider a memory foam mattress topper.