While I do not have any experience with Stern's HD I do have several sheets of PDI and one of Invisiglass. I have changed them up on numerous machines and PDI is the clear winner. No pun intended. We all have different lighting setups and in my situation PDI just seems to do the best job. Last night a guest almost put his hand through one because he didn't realize it was on. He was pretty embarrassed but we both had a good laugh. I would put them on every machine if the price was friendlier.