My delta currently uses a 8mm thick aluminum tooling plate with a circumference of 300mm. It's a big, heavy, very flat surface that my glass bed sits on. I'm going to be experimenting with the FSR kit from ultibots later this week, which includes the silicone pads and I have recessed mounts and all ready to go, but most people are using much lighter heat spreaders with them. Anyone have experience with them? My hunch is that they monitor the change in pressure, not the presence of it at all, and so if I can set the baseline to represent the heavy heat spreader, I'm hoping it'll detect the relative increase of the nozzle touching it, but I don't know if they work this way, or if they are as accurate measuring from 99 to 100 as they would be measuring from 30-31. Thoughts? Experiences?