No I didn't have any problem with water coming in the brass tube. I have a teflon liner inside the brass tube and the flex shaft heavily greased with automotive wheel bearing grease.
If you move the rudder over more, it will affect your left turns. I don't know what kind of runs you like to do with your boat, but I like to have equal performance left and right. My SH still turns to the right better, but left isn't too bad. In the pic, you can kind of see how I moved the rudder back farther. I was going to take a better pic for you, but all my AA batteries are dead and so is my charger-- guess what I get to buy before the next rc season
