"I love how they pan aftermarket (Clark) crystals. I have never had a WR issue, quality, or fit issue with a Clark or Sternkruz."
Me neither.
I bet many of these guys bought aftmkt crystals in 'rolex' packages and paid a LOT of $$ never knowing the difference. Same guys probably have a 1520/1570/75 with aftmkt stem, winding rotor axle, mainspring, center wheel, fourth wheel, CP, intermediate wheel (in autowind assembly), aftmkt case tube, gaskets etc...carefully cleaned with Ronson's and oiled with 3 in 1.
...and they all wonder why their rolex smells like a Zippo lighter.
No one even cared about this until the internet started making 'experts' out of all these fools.
I started seeing them in droves at watch shows about 15 years ago...1000 questions, no answers, and not a clue.
"If it is not Rolex it must be junk, right?"
Dat's wat ah reed on da internut.
Imho todays 'Macho Watcho' is a G Shock, not a fragile, pricey, $lickdick rolex. Hee Haw!
Btw, I've had good luck with GS crystals for years.
...but I'm still not goofy enough (yet) to jump in the water wearing a $5k "no parts for you!" wristwatch.