I found myself in a similar position back in 2018. I had a durable plastic Timex, and a reliable Citizen Eco-Drive, but wanted something "nicer".
Fast forward a few years, and I am glad I went down that route, but I recommend jumping from $50 Casio straight to $1-2K watches like CW, Seiko, or Swatch brands. Less expensive watches work, and are well made, but once you hit the $1K mark the quality is noticeably better.
These days I wear CW, Damasko, Marathon, and Jack Mason. My less expensive micros sit unloved on my dresser, not because they are bad, but because the other watches are nicer.
Neither, save a few dollars more and buy something actually interesting.
I hate my Casioak.... it's bulky, not great any anything useful, and mostly a hype watch.
The simple answer is don't buy if you have any concern about authenticity.
Luxury watches aren't necessities, so buy new or stick to a price your comfortable being ripped-off at.
I like field watches, and I agree that you can get the look for a lot less elsewhere. That's part of why I never bothered with a Khaki field watch. They are well made, but don't interest me.
By the time I'm under $200 I'll just stick to buying the known brand. Timex, or Casio both make great watches that cost slightly more than Skmei.
The hardware is made by a company that specializes in strap hardware I suspect. They batch buy hardware, and have a strap supplier throw the cheapest material possible on the hardware.
It makes sense from a business perspective. Less well-made hardware from a new supplier would likely be more expensive than just buying what everybody else buys.
I think the CW is a better option.
I think GS is a bit overrated in the watch enthusiast community. Lots of companies make great quartz watches.