Order arrived fast and on time. Durability is impressive, I have dropped these pipes far more than any others I have owned and not a single crack. That said, both pieces came with the exact same cosmetic defect near the hole in the oil pipe. Other reviewers have flagged it, and I can confirm it. This is clearly a manufacturing issue at the weld point where the bowl section and tube are fused. You can see the ‘neck’ of the join, which is typical of mass produced quartz formed on lathes and torches rather than hand finished glasswork. The weld holds structurally, but cosmetically it looks rough and unfinished.
I have also noticed slight devitrification over time. For those unfamiliar, that is when repeated high heat exposure, such as direct flame cleaning, causes quartz to crystallize microscopically, leaving a cloudy, frosted look. High purity quartz resists it better than borosilicate, but even quartz will cloud if overheated or if the annealing process during production was rushed. These are clearly machine made, not artisan pieces, and the shortcuts show.
Overall, if you want a workhorse pipe that can take abuse, it delivers. If you want flawless clarity and true handmade quality, you will need to look at artisan quartz from specialized glass shops or independent blowers, and those come at a higher price.