[pct-l] gear?

[Chase L Frantz]

How big does a pack need to be for a thru hike on the PCT?  I am
looking at ULA's Circuit backpack but not having much long distance
hiking experience I wonder if that 3,700 cubic inches would be enough,
or should I opt for the larger Catalyst. (Also by ULA) 4,600 cubic
inches.  Anyone who has an opinion on gear please let me know, for I
am still young and need all the info I can get. Chase.