Seemingly very sensitive. My first brick was measured using the test use. Application Description hairline cracks and has been impeccably exchanged through Amazon. The stone must be very hot before and between the baking operations in order to avoid stress cracking. The baking result to be proud of. Crispy base and hot pad, the one possible not distributed to close to the edge of the dough. The new stone does a good job, which suggests a failure of the first product. The wooden slide is very high compared to alternative products. The cooled stone can be cleaned easily by the way!