I'm not a fan of those kit vests but here's how I see the pro's and con's:
Pro's:
Plently of room to carry all you might need.
Kit more accessable as not all buried on top of each other.
Weight spread across whole upper body.
Smaller pockets than a pouch so less likely to snagg.
Vest works as another layer of insulation (a bit....maybe....sort of).
Con's:
No big pouch to put bigger items into.
To fit over winter kit it would have to be big...then in summer it'd flap about.
If you take your jacket off then you've not got your kit (belt pouch stays on always).
Possibley more pockets to get snagged in the forest.
People often mistake you for a photojournalist (
)
Harder items may dig into yuo as the pockets are quite thin
Pockets make wear through faster due to being thin
So.....that's all I can think of but I'm sure there's other pro's and con's.
I bought one a few years ago....tried it on and then gave it away as I ddin't like it. I think maybe a non-cammo chest rig might be more useful.
Hope that helps,
Bam.
(I'm told they are very good for fly fishing etc and that's what they were designed for....haven't tried it myself).