Fiberglass mat tissue and cellulose insulation differ in terms of material composition and insulation properties. Fiberglass mat tissue is made from fine glass fibers, while cellulose insulation is composed of recycled paper fibers treated with fire-retardant chemicals. Fiberglass mat tissue offers higher R-value, meaning it provides better thermal insulation and energy efficiency. Additionally, it is resistant to moisture and does not promote mold growth. On the other hand, cellulose insulation is more affordable, environmentally friendly, and provides better sound insulation. Ultimately, the choice between the two depends on specific insulation needs, budget, and environmental considerations.