I have one WM ARF, the Super Stunts 60 with a Irvine 72. The plane flys fine but I had one big problem on assembly. The pipe for joining the wings was too large in diameter. When I installed it into one of the wing half it stuck. Trying to remove it caused a lot of the ribs to brake. I was going to be in the Livermore, CA area soon so I took it back to the distribution center. They had to bust into 3 or 4 models to find a pipe that would fit. They did fix me up O K but it was a real pain. I saw a young fellow in a LHS recently that bought a WM trainer. He had all kinds of problems putting it together as the instructions on these aren't for the first ARF that one builds.