AER Go Pack vs Osprey Nebula

These are going to be more suitable for ‘true’ one bagging (ie when you travel without a checked bag). If you decide to opt against a checked bag, perhaps look at a packable day bag and one of your options above, or take a look at the Peak Design Travel Bag, as this is designed with photographers in mind, is effectively a big bucket of a bag, and can expand from 35-45l (although I think when expanded to the full 45l it is slightly too big for most airlines). For a daily carry, you ideally want to be looking at something 25l or less, even under 20l.

The Nebula is a good-sized pack. At 34L, I find it a good size for travel, particularly because of the TSA-approved laptop compartment. All of the dimensions of the 2019 version are the same as the previous version, but somehow weighs .3 pounds more