A quick sharp tap with a hammer always brings the cracks out so you can see them very well
I think cracks usually are pretty easy to see if they are there, also I would say that cracks are rare and you just got unlucky with the first display delivered. Glass is glass and breakage will occur when handled rough but the glass is fairly strong and not easily broken when handled correctly.

I think cracks usually are pretty easy to see if they are there, also I would say that cracks are rare and you just got unlucky with the first display delivered. Glass is glass and breakage will occur when handled rough but the glass is fairly strong and not easily broken when handled correctly.