This bag has become one of my go-to bags. It is really well-made, stiff enough not to bulge out when full, waterproof, split compartments, zippers on both sides, and attaches with no sway. It fits the space on my gravel bike perfectly too (get the measurements from Apidura's web site). When out on a day ride, I can put my wallet, keys, covid mask and phone on the narrower side of the interior division. And I put an extra jacket, food, glasses, tire kit, etc. in the larger part.
I've used the Apidura Expedition Handlebar pack just once, on an overnight gravel ride on the Olympic peninsula, for about 80 miles. It worked as I had hoped - it didn't jostle or droop with use, and its capacity was more than I had imagined. I used to use a Blackburn front roll, that clipped on with a little mechanism and held separate dry bag. And I know a number of other front bags are designed with a separate carrying harness, so I had worried that having to remove the bag to access the contents would seem like a nuisance, but really the attachment straps were easy to use. I did strategically place stuff I didn't need until camp time (sleeping bag, puffy jacket), so I didn't need frequent access anyways.
I can't speak to the long term durability of the bag, thought it's not something I'm too worried about for my use. Apidura has a good reputation, and I'm personally not doing any super long (or frequent) expeditions.
This is a beautiful bag. From the perfectly taped seams, to the softer material where it touches the seat post, the reflectors, the straps, the solid attachment to the bike, everything is excellent. The material is high tech too, light and waterproof and tough. I got the smaller one, which can fit a light sleeping bag and some clothes. For colder days, it can fit a Western Mountaineering bag, but that's about it. For all-season bikepacking, I would get the larger size. For everyday riding, it's perfect for extra layers and such, especially on longer rides.
This bag is the perfect addition to the Handlebar bag. It is exceptionally well-made which you can tell from the perfect seams, and small details all over the bag. The material is very high quality too, and tough. You need it for the small extras that have to be accessible while you ride. I don't think it can be used on its own (unless you jig something up), but attaches perfectly to the big bag. I have a Garmin 820 and light on the same Garmin arm (the light hangs below the computer), and I do have to move that assembly up to make space for the bag.