I use the longest arms. By using the outside hole I can get the most control throw. You want a lot of control surface movement on these 3d's, around 45 degrees. That's why it helps to have a radio with exponential so it's mild near the center of the sticks but still have full deflections when you want it.

The Ultimate can handle a lot of power so I don't think the Typhoon 6 would be too much. I saw they recommend an 8-3.8 prop. We use 12-6 on our Himax's. Don't know how fast it would go or how good it would hover. Also have to think how to mount it to the stick.