I tried some chest packs a few years ago and found I got line hug up on the pockets.
Maybe I was putting too much in the pockets. They fill up fast (as already mentionned).
I use a vest, moderately full and a kt bag on the bank or in the canoe.
I suppose the choice of gear really depends on the type of fishing you do and how much "stuff" you need/want/use while on the water.