Premium Mattress Topper vs 3 Copper-Infused Memory Foam Mattress Topper with Washable Cover: which is safer?

Where these two actually differ

• We flag Volatile Organic Compounds (VOC) off-gassing from polyurethane foam, Polyester cover degradation and microfiber shedding, Polyurethane foam degradation and chemical leaching with age and Water-resistant coating composition (undisclosed) on the Helix and not on the Sleepyhead.
• We flag Volatile organic compound (VOC) off-gassing from polyurethane foam, Coating degradation and microparticle shedding over time and Polyester cover pilling and synthetic fiber shedding on the Sleepyhead and not on the Helix.
• The Helix is polyurethane foam, polyester cover where the Sleepyhead is Memory foam, polyurethane foam, washable polyester cover, which is most of the difference in these two grades.
• These two are level, close enough that price and fit should decide it rather than our grade.