Haven't had a chance to use RoofBag yet.
I'm only giving you 4 stars because I haven't used the product yet so I don't know how it will work. I bought it for a trip that we ended up not taking. The online experience of buying the product was very easy and informative, and when I tried it out on my car I found it to be the correct size and as long as I get it tied down correctly, it should work. The cost was reasonable and appears to be very well made.