Enthusiasts may not be aware that Stern did not start applying thicker automotive clear coats until well after 2010. That was not a "standard" practice in the industry EVER before modern Sterns less than 5 year ago which was REQUESTED by private owners who wanted "shinier" playfields without understand the material thickness pitfalls.
The offset playfield shooter groove shown in not a demonstration of a "factory reject" and falls within the tolerances of manufacturer playfield construction. A collector might not like it, but an operator will not care.
Current pinball manufacturing playfield standards remain predominantly unchanged since the 1950s. Primary playfield equipment processes remain unchanged since the 1940s.
People are forgetting the nature of the industry in 2006 (the playfields themselves might have been built even earlier in 2005 in preparation for the production run), or were not even interested in pinball at that point in time.
This is another example of why it is important to understand pinball manufacturing history, so interested parties know what they are looking at overall and what to expect, rather than applying current collector mindsets to every single machine. We already have some new owners believing that HER machines (or HEP as described from the 80s and 90s) are the way games looked from the factory. This is a nice thought, but untrue.
There is nothing wrong with asking a pinball parts supplier for a photo of a playfield, backglass, game specific parts, or cabinet for personal inspection before purchase, except in conditions were said part is a new production still in its shipping box or container, as there are some warranty "rules" regarding breaking seals on backglasses and some playfields.
I do this frequently even with NOS parts especially if they were made in the 1990s.
I most certainly always do it with used backglasses.