I decided to give it a try and I’m so glad I did! The 12” version fits the gap perfectly with no discernible edge and the feel is seamless. The strap that it comes with to go around the bed is absurdly long, but better than being too short - it does not affect the beds ability to adjust. I do also use a horizontal bed bridge that I had gotten before this, but didn’t do the job on its own. Together, you can’t even tell that it’s a split king anymore. Highly recommend.