I have owned two Topeak wedge bags since 2013. Both previous bags were the "STW' version with the zippers on both sides. I mention those bags simply because I can comment on their durability and I would expect this bag to have a similar durability. Both bags were used for about three years before something broke. On both bags the stitching failed on the loop used to secure the seat post strap to the bag. I repaired the first one and used it for another year or so but simply elected to replace the second immediately with this bag. In all fairness, the second failure was likely do to my replacing the provided velcro strap with one made of a different material that was thinner, significantly stiffer and probably more abrasive. The loop failed shorty after I replaced the strap. I don't think there was a problem with the stitching and it would have probably lasted much longer if not for the replacement strap but I cannot be certain. Both bags were otherwise structurally sound, if a little rough looking. The fabric covering did fade and one of the front edges wore because I would brush it with my leg sometimes. Those bags, and this one, are large enough to extend beyond the edges of the saddle, so one might bump them, depending on how one rides. Never had any problems with the fixers or zippers. I have a road bike so I'm not getting the bag real muddy or anything that might foul the zipper. On this bag, the lining does stick out a bit in one spot and I have to push it in to be sure the zipper doesn't get caught. Have ridden in the rain, bags have been water resistant. Of course, I don't carry anything in the bag that it would matter so I don't really worry about it. I purchased the medium bag because it was the closest in size to the previous bags. This bag is large enough for pretty much anything most folks would need. In mine I have a spare tube, two CO2 cartridges, the inflater (small one), lever tools, allen wrench multi tool, some tube repair patches, caps for my Speedplay cleats, some spare valve stems, a couple of packs of wet wipes, and a small ziplock bag for bandaids, cash and the like. One might get a few more small items in there depending on how full one wanted to pack it. I don't think there is enough space to accommodate two tubes, but I have not tried. The bag does look a little lop-sided on the bike. Another reviewer mentioned this as well. You can see it in some of the reviewer pictures. It is due to the zipper being on only one side. I would prefer it to look a little more symmetrical, but I don't see it when I'm riding and it does not effect performance so its something I can live with. If that might be a deal breaker for someone, then they might want to look at the STW version. The zippers being on both sides make it look symmetrical. It also comes with some additional tools. Overall, I'm very happy with this bag. This bag's storage capacity is more than sufficient for my needs. I expect the durability to be good based on previous experiences with the wedge bags. Not sure if three years is great durability, but I think I may have been responsible for the failure of the last bag; it might have lasted longer. The stitching certainly seems solid so I'm giving Topeak the benefit of the doubt, plus it was starting to look a little rough anyway (faded and a little worn) though still perfectly functional.
