that's a very vunerable part of the MM...

you can very easily with your finger nail dent the insert. It will take a little abuse since it does have a clear coat on it but, it's a very soft insert.

Through trial and error, Jack and I found out the insert isn't to replaceable either. For being so soft, it's one resilient insert though. He threw everything but a kiln at the bezel and the insert wouldn't budge.

If you do damage it, you can get another but, you'll have to send the watch back to Japan to have it installed. They won't sell them out right. They run around $125