My JM Special (4") and my 625-6 Model of 1989 are both extremely well made revolvers by any standard.
Maybe it's the luck of the draw.
By the way, just because they were made a few years ago does NOT make them superior. I have had several 1980's Smiths that were "less than perfect". In fact, back in the sixties a friend had a brand new Model 60 that wouldn't even allow the cylinder to be closed on factory loads. It was headspaced too tightly for cartridges (factory). He sent it back and they replaced the cylinder but stated they found nothing wrong with it (he had marked the old cylinder).
Frankly, I really like my modern Smith's as well as my older models.
Dale53