If you believe in keeping it simple, the Bandolier is a minimalist's dream come true. Comfortably holds two fly boxes in the main compartment and two side pockets conveniently hold accessories . Two ZS retractor stations (great for nipper and floatant attachment), ambidextrous hemostat station, foam fly patch and tippet holder cover all your key accessories. ZS2 version now includes a molle modular attachment station allowing integration with ZS2 accessories.
I think this is pretty good for getting out in the summer with little equipment, my only gripe with this one is that it could be a little bit deeper. When you open it, you've got spaces for about two slim fly boxes, it'd be nice if it were a few inches deeper.
I originally got this pack because I couldn't wear my hip pack while carrying my daughter on my back (Osprey Poco Plus Child Carrier). It has since turned into my preferred choice for every trip when I pack light or don't need to worry about submerging my gear in water..
I typically max out the storage of this with the following:
Umpqua UPG LT Big Fly Box
Loon Big Water Drops (split shots)
If you're looking for something that's not bulky and super lightweight, this is a great option. If you're someone that like to pack gopros, snacks, beer, etc. Look elsewhere.