I thought the Canondale bag opened from the front, there seens to be a zipper there. Not sure now.
Topeak changed their mounts a couple years ago. My bag has the old one, same as shown in the picture of the discontinued bag you've posted. The new system is the one with the yellow button. I've posted a link to the bag I have above, post #16. What questions do you have about my bag? I haven't done any research on the new system yet, are the bad reviews about the new or old system?