Acrylic bathtub liners are the better quality tub liner. Some liners are made of PVC plastic and are not as attractive or durable as acrylic bathtub liners. Whether acrylic or plastic, bathtub liners are designed to cover up problems with the original tub. Unfortunately, tub liners can cause even more problems over time. Bathtub liners are more expensive and take longer to install than tub refinishing. Even an acrylic tub will not look like real porcelain...it will still look artificial. Lastly, tub liners can leak and lead to the growth of mold and mildew.