Follow-up!
In Sept. of 2021, whilst chewing on some Triscuits, one of the crowns broke in half. In examining it it appears to have been created with a very shallow hole, not sitting all the way down on the 'shoulder' of the post. It was also, mostly due to the position and angle of the post, off-center, leaving the majority of the crown floating off of the front of the post. I suspect this left it structurally unsound for the pressures created by the human jaw when biting down on food.
I'm quite certain I could get it redone for either a discount or possibly free, but I'm beginning to suspect that there is a correlation between dentists who have CNC-milling tech and dentists who focus on cost-cutting and/or expansion. This is my unscientific opinion. But it's my fault for not insisting on a better fit.
I stopped going to chain dentistry outfits back in the States a long time ago, mainly because they are little more than training school for recent graduates. It's probably time for me to invest in higher quality and integrity in Mexico as well...