The problem with the rudders was that they originally drilled the holes in the blades in the wrong place. If anyone remembers the old hobie 18 system the same thing would happen to that boat if the holes were drilled incorrectly. They moved the holes in the blades and all the problems disappeared. You could probably send a note to the factory and they can tell you the proper hole placement if you wanted to make the change yourself. I replaced the blades with the new hole placement everything has been great. No more unscheduled kick ups and you can rake the rudders as far forward as you need. I found the I had to put a 1/4 inch filler in between the blade and the casting for proper rake. The boat is very sensitive to where fore aft placement of the crew. If you are to far forward in light air you WILL get weather helm.
The other problem they had with the rudders was a bad batch of casting sent from thier fabricator. But that was back in 97-98 and I'm sure all those have been taken out of use(mostly by breaking).
As far as the mast weak above the hound. Not a problem. The mast is very bendy so you need a full cut sail. I run a pretty big spin and like all boats you just have to make sure you do not uncleat the main when running the spin.