It's important to note, that, while important, we don't consider breaking strength to be an accurate indicator of how the net will hold up to normal use because the net would rarely, if ever, be tested at it's full breaking strength.
We consider abrasion resistance to be a much more important factor when determining the lifespan of a batting cage net. All batting cage nets wear over time due to ball abrasion.
If outdoors, batting cage nets also face the added challenges of Ultra Violet Rays and moisture. The batting cage nets with the longest lifespans are made of Nylon with NetSeal. You can see more about netting lifespans here.