Shell is extremely inconsistent.
About every fifth ball has a paper thin shell.
When I opened the box, I was amazed at how great the balls looked. Perfectly round and smooth with no discernible seams. Color pattern was distinctive.
In 6 months and thousands of balls, I had never broken a ball in my Spyder, but these broke so much as to render me a defenseless target even after multiple squegees. Likewise with the SP-8.
Maybe I got a bad batch, but seeing some of the other reviews. apparently there are a lot of bad batches out there.
I wish they shot as well as they looked.
Glad I only bought 500.