I've had one come off at speed on my ST1100. I happen to be looking at it just as it was letting go. Being very lucky I actually caught it with my left hand as it popped off and pulled it down into my lap without loosing it.
This was my fault. You will all learn, hopefully not the hard way that these 3-M buttons are good for just one try. If you start moving things around looking for the right spot and using the same 3-M buttons each time you too will get to see the LIP let go and sail high above you head and disapear behind you.
What you need to do is find the sweet spot and then install all new 3-M buttons and then leave it alone. And as mentioned ther is a cure time for the 3-M buttons. The ones on my GSA have been there for over 2 1/2 years.