To expand on the thought and to further lower your concern…
After buying my first 52, which was a 52-2, I started a multi-year deep dive chasing down every avenue looking fore MORE Model 52's and seeing & learning a lot along the way.
What I found countless times were 52's and 52-1's, many from estate sales, and many of them were offered in packages with one or two extra old style long extractors.
And in chasing down old correspondence in gun magazines and short articles, it seems that the basic story was that the no-dash 39 pistols certainly experienced premature extractor failure. I cannot say exactly why this happened but it is a fair bet that rough, poor and improper handling had a part in it.
When S&W elected to redesign the extractor on the 39 (and for the debut of the 59), it simply made good sense to do the same for the models 52 and 52-1.
And many owners, fans, competitors and general lovers of the 52 and 52-1 immediately called up S&W and asked to purchase a backup extractor or two for their old style 52 pistol.
…and it is exactly these extractors that we find included when these estate sales are offered. Extra parts that they hoped they would not need — and never did need.
Could the old style 52 or 52-1 extractor fail? Absolutely. It's a machined part made by humans. But prevalent? I would say it is not at all prevalent.
The 52-1 that I own was my fourth 52 and my first one with the old style extractor. It also has the best trigger of all of mine and honestly, it may have the finest trigger of any of my guns and I own many with truly elite triggers.
It's difficult for me to say which is my favorite 52, but I do believe my 52-1 is the one I enjoy best on range day.