I have the Rush 72 a great weekend bag for the summer, I would not get my winter gear in this bag, the sleeping bag would fill it! It's a very well thought out bag and useful pockets through out, the front pocket is very useful and with the ability to put kit behind it comes in handy with waterproofs. I like to keep most of my kit inside my bag.
If you plan to walk with this bag any distance, I have found it extremely comfortable, I'm 5'11" and fits me well and carries the load evenly as long as you pack it right.
i haven't used the hydration pocket for a bladder and in fact use this to put tarps in and attach my bladder on the outside for easy access for re filling etc.
the Molly points are plenty and handy for adding the odd pouch, I have two small ones for snacks and go on the body belt and my first aid kit on the side.
all in all a good bomb proof bag, it's not huge, so makes you pack only what you need, rather than, we all do it, "this might come in handy" line of thought.
hope this is of some help.