The Hitch Buddy is clearly better than the other one. If you watch the little video - it's obvious that the dolly hitches normally but also has a pair of outriggers that force it to keep square to the tug. Lets you back up without the whole thing jack knifing. Course it IS expensive as all heck and is WAY overkill for the application...
Given the lower
weight demands of the
Scamp - I suspect you could recreate one of those dollys by taking one of the small bolt together trailers and bolting a gooseneck hitch onto it. It be like driving a train though. I'm bad enough backing up as it is...
mkw