I just cleaned an acrylic crystal, prior to sticking on a screen protector which I had to cut to fit. After realising I'd made a complete hash of the trim-job, I ditched the protector and decided to see how clean/unmarked my crystal was with a 15 times loupe. Holy Guacamole! This thing looks like the surface of the moon! Very unhappy indeed and wondering if I had been responsible, with my professional lenes-cleaning kit designed for DSLRs. But I persevered with a just-out-of-the-package microfibre lens cloth and got it more or less acceptable. I then remembered another acrylic crystal in need of TLC so I brought this one out and gave it 200 gentle swirls with the cloth. Holy Macaroni! This thing is polishing up nicely! Another 200 swirls (or about 3 mins) and it's perfect! Better than when I bloody well bought it! Back to the original watch. Now perfect also and no toothpaste involved.
I've been aware for some time now that acrylic is better at resisting shattering and maintains physical integrity in a shock as well as any crystal material, but have ALWAYS been suspect about them and wondered just why Sinn would put one in as an option on a 500 quid watch when they are so hard to keep immaculate. Now I know it's because they are so easy to return to that state. I don't know if I'm exactly an advocate, but tonight was very re-assuring and I won't be put off from a purchase by this material again. Anyone out there actively prefer acrylic? Speedmaster owners speak up!