Customers report mixed opinions on comfort, with some finding it comfortable and others feeling the plastic tubes. The product's size is a significant concern, with many reviews stating it does not fit a king-size mattress as advertised. While some users praise the temperature control for providing warmth, others find it barely heats up. Performance reviews are also mixed, with some experiencing effective heating and cooling, while others note issues like leaks and a lack of noticeable temperature difference. Value is questioned due to the sizing and performance issues.