Yes, I currently have one installed. For me all it results in is a larger shelf, for want of a better term, where more of my hand presses up and into the control box and bears the weight. For me, the end result is most of the top of my hand becomes a "hot spot" over the course of a few hours rather than just certain areas on the knuckles/top of my thumb and index finger.
Before I found the printed hand stop, I tried making one of my own. My first attempt involved building up a ring with golf club grip wrap. That didn't work as well as hoped. The next attempt was a cross section of pool noodle wrapped with electrical tape, then removed and replaced with duct tape, then some other vinyl tape I found at a hardware store. These were all met with varying degrees of success as the pool noodle either compressed too much or not enough depending on the tape used. I have to say the printed hand stop works best as intended, but still falls short for me.
My issues are my own and largely due to a history of neck and shoulder issues from a car accident some 30 years ago. I'm also the 5"11 guy who wears large shirts, but either has to buy XL or "long" or "tall" size shirts otherwise the sleeves are way too short. That's because my shoulder to elbow length is longer than average ("monkey arms" as my sister used to say growing up). There's just something different about how the detector balances on my arm and in my hand vs. others with shorter wingspans and shoulders with less mileage on them.
I sometimes hunt with a couple guys that both swing a Nox, Both are maybe 5'8" or 5'9" and have arm lengths closer to what you'd see on the average person. They both can hunt all day long without issue whereas I'm done for in about three hours.