I am headed out to the AT on Tuesday for 4 days - 40 miles (Springer to Neel's Gap). I just purchased my first internal framed back, I was using a VERY old Kelty external for years, so I am excited. Well my new pack has pockets on each side for bottles (typical) as well as a seperate compartment for a hydration bladder. The bottles I have are 48oz Nalgene's equaling 96 or almost 3 liters. I don't currently have a hydration bladder. Should I make the investment into a hydration bladder of rthis trip or is it overkill?

We are using a Katadyn gravity filter so we can fill up accordingly. I've read some articles stating that you shouldn't carry more than 2-3 liters at a time, other say carry as much as you can. I just wanted some input from those who actually hike this area