I agree with you about the alarm gear and have fitted it to a few of my coaches. I've had only one problem, and that's probably down to clumsy handling, but the "flags" which are (as they should be) just proud of the coach sides tend to get caught on extraneous bits and pieces, are bent and with straightening each time that happens eventually break off. In fact I've now taken to removing the cast flags and soldering my own on the ends with 70 degree low melt or even glue which tends to break away if caught up on something, allowing for easy replacement.
Brian