Agreed, same thing happened to pops and mine on our front racks last week. As they sit in the sun the buldged to the point they where very difficult to remove.... NO leaks!!!I haven't used Kolpin products so I can't comment on them. I do have Rotopax fuel packs and have had no leaks with them. They have pressured up and swelled up to the point I thought they could burst but still no leaks. It was difficult to release them from the mounts as they got very tight when packs swelled up. I mount them flat on my front storage box.