I own the Travel Backpack, which in the interests of fairness I just reviewed (5 stars). Compared to the quality of that bag, these packing cubes are... disappointing.
The quality is acceptable. I'm not saying these are terrible, they're actually fairly typical. But they're priced as high-end packing cubes, and I don't feel that they deliver on their cost. I don't have any confidence they'll last even half the lifetime of the bag, and when I have to replace them I'll be looking at other options.
Although not able to travel at the moment, I practice packed with my new compression cubes and my whole world is rocked. Amazing. A tidy space and I was able to pack more than I had thought in my carryon. I might need another set for my personal item and then I'll never check another bag!
I use packing bags for clothes while backpacking. This bag size holds all the clothes you dare carry on a 7 day trip. The "dirty side," and "clean side" design is ideal and the bag weighs next to nothing. As for durability, only time will tell but after the first two adventures, all is well.
I bought 5 different packing cubes. I kept these. If I could change anything the only thing I would change would be to have 1 additional compression zipper that compressed half as much. You're not going to find that on anything else either, so 5 stars still.