I'm on my 3rd UCD46. I love these planes but I have a tendency to get a little wild on occasion and have an incident that results in my carrying the plane home in a paper bag. But they really are great planes and I love to fly them. I have mine set up with a Saito 82 and a CG of 5 5/8" I works great there. My others have had similar CG. From 5 1/4 to 5 3/4. This is one of the easiest landing planes I've ever seen and yet it can do the wildest 3d stuff ever. It's not a perfect plane but it's a darn nice one. And it's very forgiving. The CG is very flexible and anywhere in the 5 1/4 to 6 range really is good enough.
Thanks,
Barry