RE: Carl Goldberg Kits
The Japanese manufacturers raised the bar of excellence in virtually every field in which they endeavored. That's what you have to do when you intend to penetrate a market that has already developed its old trustworthy names (USA). They did a fine job at it too.
The absolute crudest kits I have ever seen were the 1960's control line kits that were produced by PDQ Models of Millville, NJ, USA. Their crudeness is beyond description. However, I must say that the models, once built according to their rough plans, were very good flying models.
The only recently offered model (20 years ago) that approached the PDQ kits was a Global Birdie Ten kit that I bought. Since the airfoil wasn't symmetrical, I sold it unbuilt. Had it had a symmetrical airfoil, I would have persisted and built the model. I figured that by the time I reengineered the model to my specs., it would have been less work to just design and build my own version of the Dirty Birdy.
Ed Cregger