What is a good cubic inch capacity for a general/all-purpose (including possible foot bugout scenarios) BOB? Obviously, it shouldn't be too large or too small. 2,000cu in? 2,600cu in? I figure must haves are built in padded belts and hydration systems. I have ELIMINATED my options to the following: 1. 1,334 - Blackhawk Patrol 60PP00 Pack 2. 2,000 - Blackhawk 100oz X-1 RAPTOR 3 Day Assault Pack 3. 2,135 - SnugPak Sleeka Force 35 Backpack 4. 2,300 - Kelty Strike 2300 Tactical Backpack 5. 2,440 - SnugPak Stanima 40 Backpack 6. 2,500 - Kelty Raven 2500 Tactical Backpack 7. 2,592 - CamelBak 61077 Motherlode 500 Cargo & Hydration Pack Any positives or negatives (especially regarding brand reputations). Thanks.