I recently have been itching for a vintage sub (acrylic) having sold my first rolex, a glossy 5513, years ago. I modded an existing crystal to get a feel for it and decided to order the crystal shown in this thread. First off, the $30 shipping stung but 2 days from HK to PA was pretty unexpected so i'll survive. The swap is easy w/ basic tools. I also have a proper pressure testing setup so was able to confirm. Full disclosure, it did not pass initially w/ a crystal leak. I didn't notice anything on the watch that would have caused this (previously w/ the sapphire it was fine) so I added crystal adhesive to the base and after that it passed a -.5/+5bar vac/pressure test w/o any issues. Confirmed in a water tester as well.
Most importantly, I love the look. It's tall (if i had a complaint it would be this) but it distorts the light so well. Really fun and also, as mentioned in this thread, I think it bring out the gloss of the dial way more than sapphire. Also love that acrylic doesn't fingerprint up as much... yes it scratches but it doesn't really smudge.
I bought an extra crystal in case I feel compelled to put it on the lathe and try to reduce the height a bit. it's a $60 crystal so a little roll of the dice but I kinda want to try and the intrusive thoughts to just do it will probably in. I'll report back if i do but for now enjoying the mod.
-Matt