One slip raising the mast letting it go to one side inadvertantly or having something catch on something and you'll break the plate. You might not like it so much at that point... Once you do that you learn to keep a spare in your tool box. I've broken one raising the mast, and I've had one shatter/break into pieces while sailing which was interesting...

I very much prefer the system on my 20 in contrast, even though the mast needs to be rotated.