Were they testing with Shimano/Sram cassette? If it's one of those aliexpress cassette (Sunshine, ztto, goldix etc.) shifting is always finicky, sometimes the cassette itself is loose (it's not riveted but screwed in with cheap screws. The ramps are bad etc.
Larger gap between pads does have an advantage though, usually results in less brake pad rubbing. Although if the throw is too long it might not be as responsive as Shimano brakes. I also did notice that using genuine hydraulic hose from shimano seems to be better than those cheap ones I found on Aliexpress for like a few quids per meter.
Again thanks for your hard work, hoping somebody like Trace Velo can review that groupset in the near future