It really depends on the type of traveling or activities you're doing. I love a backpack that I can zip fully open because I'm extremely disorganized so it really helps me to keep everything organized while backpacking. However, those kinds of backpacks are not meant to be worn for hours on end or for extreme/strenuous activity. The longest I've ever walked with one of those is maybe an hour or two and it was on a road. If you plan on hiking more rugged terrain and be wearing your backpack more longterm, you want to prioritize a good support system for your back. Also, a top loading rucksack kind of backpack will theoretically last longer because you don't have to worry about zippers breaking.So, for example, if I were backpacking around Southeast Asia and traveling by public transport and staying in hostels and guesthouses, I would use a front-loading backpack that zips open all the way. If I were backpacking around Nepal and knew that for a significant portion of that time I would be trekking from village to village in the Himalayas, I would use a top-loading rucksack backpack. I hope that helps!
It really depends on the type of traveling or activities you're doing. I love a backpack that I can zip fully open because I'm extremely disorganized so it really helps me to keep everything organized while backpacking. However, those kinds of backpacks are not meant to be worn for hours on end or for extreme/strenuous activity. The longest I've ever walked with one of those is maybe an hour or two and it was on a road. If you plan on hiking more rugged terrain and be wearing your backpack more longterm, you want to prioritize a good support system for your back. Also, a top loading rucksack kind of backpack will theoretically last longer because you don't have to worry about zippers breaking. So, for example, if I were backpacking around Southeast Asia and traveling by public transport and staying in hostels and guesthouses, I would use a front-loading backpack that zips open all the way. If I were backpacking around Nepal and knew that for a significant portion of that time I would be trekking from village to village in the Himalayas, I would use a top-loading rucksack backpack. I hope that helps!