A mate has an Osprey. They don't hold the stated capacity. His 2l is really only a 1.5l at best. Not much of a problem really.
Easy to fill, not so easy to clean if you put powders in. With the stiff back to the bladder easier to get in to a pack. Some people don't like the stiff back on their back. I didn't notice much difference when I tried it on. The bite valve is good. Doesn't dribble. Handy with the magnet on the chest strap rather than clipping it into the usual clip on the shoulder strap.
Only downside to all bladders except Camelbak is that stockists are more limited. You can get anything online. But if you turn up at a trail center shop or an event and need spares, everyone will stick Camelbak.