I have the OEM divider and I think it's great. I also really like the molle style holes where you can strap a bunch of stuff up against it (I strap my toolboxes to it). I also have the OEM soft cover and they work great together (no trimming required).
Lastly, the unit itself feels nice and sturdy and I think its worth the asking price.
Instead of trimming, I cut slots into the sides of the rail mounts for the divider (the factory configuration uses holes in the top/ bottom depending on how you install the mount. Since the top member of the bed divider is standard extruded aluminum t-slot rail, I can now put the t-bolts into a side t-slot, vs the top/bottom. The benefit here is that this eliminates interference between the threaded knobs with my retractable tonneau by shifting them to the side vs top/bottom. It’s also super easy to remove and the divider can also be easily installed horizontal if I need to use the full bed length by shifting the t-bolts to a side slot in the top member. I don’t know why this isn’t the factory design.