RE: Four Blade Props
I have nothing against muti blade props. In fact, I am building an all composite 80" BF109G that will have my scale size and shape carbon blades. Variable pitch (manual adj)
I have a home made gear down system for my 108. If that fails I have purchased a Moki 210, which should handle the 20" arc blade.
All that matters if it it works for you and your having fun.
Steve