Lol, I just got my Yingmin GB-187-S. This is my first GB-187 series, so I can't compare to the OG 187.
Shipping was superb (bubble wrap on the exterior of the box!). The Perc on the 187 is stunning. Perfectly in every way, the cuts are awesome. The mouthpiece is also an improvement over the FC-187.
The base on both pieces appears to be nearly the same diameter. The only main differences aside from the perc that I see, is that my FC-187 is about 0.25 inches taller, and the FC-187 is maybe 0.5 to 1.0mm thicker glass. Still the GB-187-S is an improvement over my FC-187v1 with it's poorly cut perc
But here's some pictures of the FC-187v1 vs the GB-187-S
FC-187v1 on the left, GB-187-S on the right. - note the height difference.
Oodly enough, the mouthpieces are both angled nearly identically
Check out the difference in build quality on these percs. The FC-187 is on the left
And lastly, a great shot of how a knockoff matrix perc SHOULD look like
Personally, I'm going to sell my FC-187 to a combusting friend who REALLY likes the design, and keep the GB-187-S for myself