I built a two-stage version with 18mm engine mounts. I didn't add any nose weight, and it flies well without it.
The one time I flew it on a B6-0 to a C6-3, it nearly went to the big portapad in the sky. It disappeared completely out of sight, and the small size combined with streamer recovery makes it difficult to spot on the way down. Someone just happened to be walking by on the far edge of the field and picked it up, or we likely never would have found it-- we weren't looking in the right area at all.