I almost purchased the same bag and rack as the OP from Amazon, but then found a similar alternative at an LBS. The bag and rack are Sunlite/IBERA PakRak products. The bag is similar in size and function to the Topeak DXP bag with foldout panniers. The reason I went with the Sunlite setup was that I liked its quick release setup better than the rail setup on the Topeak bag/rack. It seems to be well made, is secure, and doesn't rattle when I ride over rough patches. I'm curious to see if it holds up as well as the Topeak products. The few reviews I could find online for the Sunlite bag and rack seem to be positive.