For $20 I have no complaints. Not much you can buy today for that price.
I see what you mean now about the prop sizes being different. I think
more than anything that's probably it.
I've had no problems with stalling on the SW after adding some nose weight.
The larger wing solved the death spiral problem and also gave me the nose
weight I needed.
The original SW wings were chopped off completely and some of the top
fuselage was removed.