I got this pack last summer for dirt biking after finding the Nomad too small (see my review) and so far it has lived up to the task. It's well-built, which makes it a tad on the hefty side, but the weight is worth the ability to survive multiple crashes without failure. At 26 liters, it's bigger than any mountain biking pack I have owned or used, but it might be perfect if you needed, say, a burly pack for MTB touring or all-day winter rides with tons of gear. In the Apex, I can fit a spare dirt bike tube (way bigger than a MTB tube), a tool kit, a bolt kit, an emergency blanket, ski straps, food, sunglasses, a hat, a small first aid kit, 40 feet of 1000lb test static line, carabiners, a rain jacket, and a bunch of other small items. That's all in addition to the full 100oz water reservoir, so when I say it is a big bike pack, I mean it. The reservoir is a Hydrapak Shape-Shift bladder with the quick disconnect hose, and truly a great piece of tech. The center baffle keeps the bladder from barreling, so it stays flatter in the pack, and the top slide-lock closure makes filling and cleaning super simple. The back panel features two firm ridges of vented foam that keep the pack away from your skin so air can circulate; some say it is irritating but I've worn it for 6 hours at a time with 20lbs of gear and never felt uncomfortable. So far, I have absolutely no complaints about this pack. If you're looking for a mountain bike pack, I would honestly recommend a smaller one first (like the Nomad or smaller), unless you know for sure you will be carrying a ton of stuff. But if you do need a big pack, the Apex is a well-made bike pack with tons of space and great features, and it looks like it will last a long time.