Just to add to this thread...I finally took the kit I'd kept in the closet and built it over the winter. Using an ASP 61 4-stroke and and Ohio Superstar tail wheel mine came out a 5lbs 11oz. The engine pulls her around with authority although you are flying on the wing. While its very fast it will not maintain verticle. Its so small that with my tired eyes it goes out of sight in a hurry if you're not careful. The stock gear was so flimsy that a couple of rough landings pretty well flattened it out. I reshaped it but decided to remove and replace with a Du-bro nylon main gear. This also adds height which will help since a 12x6 prop mowed the runway with the stock gear. So far about 10 flights and I'm starting to like her!