Firstly, just wanted to say that they are great...although too big for my small car boot (I know...its supposed to be towed on a bike, but my excuse is that I have a 7 week old and she can't go on the road yet).
I am looking to buy the Transport Bag, so I can attach it to a roof rack, but it seems SO expensive. Do you have one? Is it worth the money? Could you think of anything else I could use instead?