RE: V-Tail surface movements
I also am just dealing with my first V tails. I have found that if I take the right half V and roll it vertical the moving surface should perform just like a standard rudder with the left one operating opposite. I was reinstalling my radio in one yesterday and the elevator function was back wards and so I just reversed the servos but then my rudder function was backwards. I finally realized that I had the servos plugged into the wrong functions and when I plugged the appropriate servo into the rudder and elevator functions everything was fine. I have really resisted working with V tails but now it is over and no problems.
Your 15-300 class sound great.