I have used the Ultimate Direction Marathon in 2 half marathons, 1 marathon, and numerous training runs putting in over 110 miles while wearing the vest. Comfort has been great with no areas of chaffing or rubbing. Durability has been good with no busted buckles or worn straps and practicality is also good with easy access to bottles and food. I still notice that it rides a little high compared to other packs and this can be a minor annoyance and I do feel like heavier items in the pack cause it to bounce more than other packs I have used. Read on for my full update.