Big packs in front are a pain when using stripping baskets because they get in the way; two compartments ala mae west drive me crazy when rowing because they hinder arm motion when rowing; and I like a traditional vest when Spey casting to spread the stuff out wide and thin (provided I don't stuff it) besides it's typically not too hot while steelheading.
That being said my favorite was a "riversmith" chest pack with removable bakpack that was poly impregnated nylon with multiple compartments smartly designed. I think the company went out of business unfortunately or I'd buy another in a minute.
I use the Patagonia double haul sling chestpack a lot especially when the water bladder is important (tropics, etc). I prefer the two-shoulder river smith strap system over the one-shoulder sling of the double haul which puts more pressure on one shoulder while the other spreads the load.
I don't like the styling to look too fancy so that rules out some brands mentioned by others for me.
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