So my old gc2b binder has gotten loved and worn so much that it's seams have pretty much fallen apart. They started to rip when I first got it thanks to my shoulders, and it took them maybe 6 months to fall apart so much that it's starting to get awkward to wear. So I ordered a new one, it's still my favorite binder on the market.
I've been pleasantly surprised that it looks like they reinforced the seams, particularly in those areas where my old one started to pop. The seams are thicker and look much stronger, and this binder's seams don't creak or anything when I put it on, unlike my previous one. I of course just got it and can't speak for how much stronger they are, but they've definitely done something to try to fix the longevity issues.
So if you wanted to try GC2B but was worried about durability, it may be worth it to order one now, looks like it'll last much longer.