It could just be individual blades, but the pre-2016 (it was a 2014 one) felt like a fast all wood blade. Very flexy, but can be an issue with shorter stroke shots when you want it to be more direct but it still flexes. It's powerful when hit very, very hard, but otherwise rather slow. The newer one (a 2020) felt more hollow, didn't feel like it had as much of a powerful slingshot effect with very hard loops, but overall a bit faster.
My national W968 felt like a stiffer and faster version of the 2014 blade. It's much more crisp and faster with softer shots, but still has a really nice slingshot effect with very hard loops. It was very hard to control when I switched from the 2014 HL5 to the W968, took about 2 months to fully adjust because of how different they are.
