The "GS-X equivalent" I'm speaking of isn't DIY, it's a Headamp's Gilmore Reference, which is the same balanced circuit of the GS-X but with some differences in components and such. Justin may say way better.
If you're referring to the B22, then yes, however it's a well known circuit which a lot of people builds on kit boards using the same sourced parts. If made right, should sound very much the same I guess. However my experience is very limited, I've only listened to mine and a friend's one, made by a professional builder. I think they sound quite similar, being the differences more attributable to the source used than anything else. Both, the B22 and the GS are quite good showing upstream components differences, and can drive about anything.