I have not tried silicone spacers. I did buy stiffer springs. I also tried to mount the bed via three points instead of four, but that actually made it worse. My bed is a bit convex, high in the middle. It's not been a huge deal, but sometimes I have to run clearance tight in the center if I am going to do a large print. On tall prints I struggle with the bed being on four posts with no lateral support, so the top of print tends to move around.