the G2S is a "budget" version of the SSA. same design, same mold etc, they just don't put AS MUCH time into stoning and wire cutting them perfectly smooth. They also batch test them instead of individual testing. Otherwise they're the same trigger.

they don't include the slave pin in the box and use a slightly different hammer pin retention spring. basically it's a trimmed down SSA without all of the fancy package ins and aren't stoned as much. after 500 rounds through them you'll never feel the difference. I have both and I can't tell a lick of difference after a few hundo rounds through it