I don't know what a GA 1 or GA 2 are, so I cannot comment.
For general water flying, I wear a Mustang inflatable, which suits my needs very well. (though it is an automatic inflatable, and when I got to the amphib yesterday to go for a fly, it had deployed itself. Perhaps a bit to damp in there on the previous rainy day! It's reset as a manual now!)
For my cold overwater flying, I have a Mustang Ocean Class floater suit, and more recently a Helly Hanson floater suit. Both excellent, but a little cumbersome and very warm in a heated cabin.
While flying in Hong Kong last summer, I was provided a Switlick inflatable with all the bells and whistles (literally!). Super product, but probably rather expensive.
It all depends what kind of flying you're doing, and your budget...