To see what a GR2 34L and 40L look like on someone about 5’8”, you can watch my video above or read on. The Differences SimplifiedLooking at the specs, the GR2 40L is only two inches taller than the 34L, with all the other dimensions the same. If you already have a larger (30 liter or more) backpack filled to capacity – particularly with electronics – go with the GR2 40L. Personally, the smaller laptop pocket was a deal-breaker on the GR2 34L I was maxing in the front compartments. If you’re shorter than 5’7” then the added space of the 40L won’t be worth the discomfort during travel.