I just came back from an outdoor shop, and I saw that Vaude has a rectangular track for the bottom hook, so you'll have more possibilities to adjust the position of the hook, when compared to the new Ortlieb single track. The website lists prices, weight, and volume by the pair, so it might be confusing.
There is a lightweight version and a standard version. The lightweight specs look very light, although the material is thinner. The standard version is slightly heavier than Ortlieb. The lightweight version's closure seems similar to the Ortlieb roller, where the rolled ends clip together. The standard version has in addition clips on the side if you want to attach a shoulder strap separately from the top closure. One of the annoyances of the Ortlieb closure is that it tends to unroll if you're using the shoulder strap. The standard version also looks like it has a beefier back plate compared to Ortlieb. Ortlieb has exposed fabric on the back, which is being worn thin by rubbing on a protrusion on my rear rack. I'm going to have to add some Seam Grip and a piece of tape to cover up the worn area.
https://www.vaude.com/en-INT/Product...mber=129514590
https://www.vaude.com/en-INT/Product...mber=124931250