I went with the Camelbak MULE. works great, initially had prbs w/ it leaking from the bite valve, but no further problems now. Sometimes I debate about getting the HAWG, b/c I like to carry everything "just in case" but I don't ride all day epics.

I carry:
Multi tool
Tire pump
tube of slime for tubeless tires
first aid kit
3 or 4 clif bars, a few power gels
Leatherman Multitool
flashlight
emergency blanket
My wallet
chaintool
My car keys
tire levers
emergency whistle

Yea I pretty much carry everything you have listed plus more in my HAWG. It wouldnt have been an issue if my ride buddy would hurry and get a camelbak so we can split the load.

Hmm time for contents list: 3 pairs of gloves, Gerber multi-tool, Topeak Macgyver, ipod+headphones, keys, watch, Topeak toolbar, Pocket knife, Extra cell phone battery, prescip glasses case, oakley xmetal glasses case. I absolutely love the bungee cords, last night I had my hoodie still at work from the morning ride, and I wasn't going to wear it. It's a 5x hoodie. I just folded it up and stuck it under the bungees. Rode back to my friends house without it even budging. So far it goes great things for me. The only complaint I really have it, a full reservoir will make the bag fit you differently (I ride with it empty alot).

edit: Also, a Balaclava.

I know what you mean. Its hard to get the top flap closed of the reservior holder, so when its full I just leave the top open. Later in the ride I am able to close it though

3 gloves??? weird.

I haven't used the bungee cords yet, but I know I will when I hit the epic trails in the cold weather. Gonna love 'em