Have to admit I disagree with you on this one point. Try flying a Sagitta 600, a Spirit, a Gnome 2M, an Oly II, and a Prodigy, in succession. They all fly quite differently!
-Sagitta 600 needs to keep speed up just a bit or tail will wag. But if you do it right it's not annoying.
-Spirit has annoying tail wag in thermals and takes more work for the pilot when thermalling. The wag is somehow different than the Sagitta's.
-The Gnome has a tail wag which is somehow not very annoying, and is lots of fun to fly.
-The Oly II is best when slow and has very friendly, steady handling.
-The Prodigy has pretty good performance if flown perfectly. But it will try to snap roll if you have an impure thought.
The airfoils are a big part of this, but not the whole story.
Originally Posted by northwest
(because most RES planes handle essentially the same). .