Whilst waiting for this item to come I was using a carrier bag to line the car seat with and a towel on top.
This then arrived. Whilst it looks better than with a bag and towel I think the a bag and towel is more practical. In the picture it looked quite sturdy, if not a little rigid so I thought it would fit quite nicely. What I find is that as it is just made up of material it is flimsy and squashes and creases when you put your child in place.
Perhaps the design would be better if they had inserted a piece of plastic to give it more shape so that it would stay in place.
Overall thought - if your more bothered about how things look then go for it, if you don't then keep to a carrier bag and a nicely placed handtowel on the top.