I had a larger piece crack off the top rim of my 1st sapphire dish, kept using it even though I had bought one of the NV SIC dishes as backup. Ordered a new sapphire, keep the cracked one as a backup. The problem with continuing to use the cracked one, was mine being a bit deeper, I had repeated oil going up and over, and into the titanium DCup dish holder, and that adds too much cleanup time. I believe knowing the sapphire is a clean surface makes it worth it to me, especially after I read about it, and it’s main fault of being susceptible to temperature SHOCK.
As I always cough after a hit, I make sure my head is turned away from my dish, human spit is probably 300f cooler then the dish. That’s not how mine cracked, but I NEVER want to experience a $150.00 COUGH!