Osprey  Rev 1.5 Hydration Pack - 51 fl. oz.

I'll admit I'm writing this after 2 mountain bike rides, but it worked so well that I wanted to share. I wore it once on a 10 mile pre-ride just to make sure everything worked. I was expecting to have to do a lot of adjusting, but with the exception of positioning the double front straps I never touched it. The 2nd ride was on a muddy and brutal 65 mile mountain bike race. Again, I was expecting to have to adjust something over the course of those many hours, but not once did I have to. Like other reviewers, I forgot it was there. It fits very well, and I had it full loaded: all 1.5L of water to begin (and several refills), my keys, phone, about a dozen gels/bars stuffed in the various pockets, and because the mountain conditions called for a fierce storm (that never materialized), I also stuffed a lightweight shell and an extra pair of wool socks (in ziplocs) for insurance (those clothes went in the bladder compartment). Yes, all of that was pretty tight for this minimalist pack, but it worked and I didn't have one issue with fit, rubbing, etc. It worked extremely well. I also have the Manta 28 hydration pack, and that works equally well for a larger/daypack arrangement with more capacity- much different design and features. This Rev 1.5 weighs about 1/3 of the Manta to begin with and I'd say that it fit better. I was interested how it would "ride" while I was cycling without the added stability of a waist strap - but again, this thing fit so comfortably it doesn't need that extra complication, weight or feature. And, you can't fill it so full so that you have something heavy to begin with. The bladder system with the "holster" and the quick connect also was great for quick refills. The magnetic bite valve is the feature I like the most on the Osprey packs and the 1.5 liters was able to get me to the next wilderness aid station no problem (approx 1.5 - 2.0 hours of cycling; I also had a 22 oz bottle on my bike). Some imperfections/needed improvements: -the digiflip phone pocket is good in concept but pretty poor in execution; like other reviewers have said, it's not even close to going to protect anything from liquid - including rain, your own sweat or even some mis-fires with drinking dribbling. Also, when you put something rigid in that pocket, the fit on that shoulder strap gets ruined, since that's the part of the strap that MOST needs to stay curved. I ended up putting the phone in a ziploc in the zippered compartment and use the digiflip pocket for a course map and extra gels. I guess it could of course work in some situations. I think conceptually and ergonomically the only flat place to put an easy-access phone pocket like that is across the chest (probably awkward too) or the waist belt (non-existent on this model). In the future if I don't need the extra pockets for gels, I'll likely just take that pocket off (luckily it's fully removable) - even on its own it's kind of bulky compared to how svelte the rest of the pack is. -I could only get the white color variation, and some parts of the white fabric permanently absorbed some of the copious mud we encountered on the race. Odd is the fact that some fabric washed completely clean, but the stretchy fabric got permanently stained. Why they don't offer the Rev in any darker colors that hide stains of all sorts is beyond me - all the colors are "look at me" bright. Finally, personal preference here - I'm a pocket person, and I wish I had just a little more built in organization, so I might try the Rev 6 . But I really wanted to get as minimal as I could, and this 1.5 model ended up being able to stretch to allow some extras I needed that I didn't think would work to begin with. I didn't even end up using the front panel bungee cord, which of course adds some extra capacity when needed (but having had stuff fall out and into a wheel when mountain biking, I'd only use that when running/hiking). Hope this helps. Would totally buy again. Another great Osprey pack and would give it an A+ for fit and an A- for design. -

It pains me to write such a poor review on a brand that I absolutely love, but this pack completely failed me. There is no arguing that the pack is aesthetically pleasing, and upon trying it on at home with the reservoir filled to its 1.5L capacity, the fit was perfect. As an avid trail runner, this pack seemed to be the ideal compact, minimalist running vest. But now the bad part.... Roughly halfway into a 10-mile trail run, on the packs maiden voyage, I began to feel water running down my back. At first, just a trickle, and then moments later, the flood gates opened. Somehow, the bladder on the inside had sprung a leak around the base where the hose attaches. It appeared the plastic that the bladder is made out of had worn down to the point where a hole, the size of a pinhead, had formed. I must reiterate, this occurred during the very first use of the pack. I must also add that previous to taking the pack out, I did a thorough check of the equipment, to ensure everything was in working order (out on the hot trails here in SoCal, H2O is a major lifeline). And, just to add insult to injury, the water that had leaked all over the inside of the pack caused the lime-green interior color to seep onto the outside of the pack, discoloring the grey exterior into a strange looking yellow/brownish color. To sum things up, this pack appeared to be incredibly sturdy, and because it was built by Osprey, I had only high expectations for its performance ability on rugged terrain. Perhaps I just purchased a lemon, but it's really hard to tell.. I'll be returning this pack and wont be buying another- I would hate for it to fail me again during a trail run or marathon. Unfortunately, Osprey may have missed the mark on this one, or perhaps I'm just unlucky.