I can verify this is true. My gal bought me the classic red and white lion mark shirt from PWT, was disappointed with the quality, then got me an original off a reputable eBay seller.
She kept the PWT version, and a couple years later, the differences in color and thread quality are even more noticeable than before. You might end up paying twice as much, but the real thing is worth it.
The NJPW originals are slightly smaller due to the cultural size contrast, so a Japanese large is more akin to an American medium. Keep that in mind when ordering.