Hey Adam,
I'm building the HR3 and also went with an O.S. 61. Can you tell me how you went about reinforcing the horizontal stab, engine box, and ailerons, etc.? I have read a bunch of threads here and am questioning what I should do. I saw where some guys laminated carbon on the stab, but other opted for the carbon rods. Since you have the exact same set up I will have, I was interested to see what you have done to address these things.......I'm not new to the hobby, but definitely don't know a lot about how to make needed mods............was almost thinking about going back and getting the new O.S. 55.