This bag fits really well & is comfortable to wear. I find the side pouches a bit restrictive for water bottles so put my bottle inside and use the side pouches for tissues etc. The bag will comfortably hold a 500ml bottle inside.
Love the extra zipped pocket on the back - I wish all Pacsafe backpacks had this feature. It's so handy to be able to reach my phone without opening the main compartment.
Other 'likes' I'd like to see would be a keychain holder on the inside and a chest strap (hence 4.5 stars!)
I have the largest 17L backback for when I need to carry more but this 8L is more practical for carrying everyday essentials, with room to spare.