Mature Metal Jailbird: Security Screw Compared to Padlock

Here’s the short version: I’m approaching one year in nearly full time chastity. The longer I remain locked, the more my wife enjoys snuggling and pressing her body against mine. She REALLY loves it when my cage “jumps” - her word, not mine - because she gets me so excited. What she really DOESN’T enjoy is the padlock from the Mature Metal Jailbird poking her as she pushes back. I’m using the Abus padlock from MM and the sharp edges along with its position on top aren’t very comfortable for her. After getting poked once again last night, she asked if there was another option - so I told her about the security screw/key. Here’s my question(s) for those that use/have used the security screw on a MM product: I’m assuming it has a special pattern/method similar to the security lug nuts on vehicles? Or is it easy to undo without the key? Does the screw back out or seize up from continual wear? Will it “smooth” things out down there? While I’ve never had an issue where I needed out immediately, having a screw I can’t remove versus a padlock that can be cut is a little daunting, to say the least. Any other tips or suggestions?