I flew without wheel pants for the longest time on my radiocraft extra. For vertical down lines, power off, a 4% mix of down elev to throttle was required to hold a down vertical line. I then added wheel pants to the plane and without changing the mix the plane was tucking more and more as it gained speed. I reduced the mix to 1% and now it holds a perfect vertical down line. So for me there was a noticable difference, and wheel pants made my plane fly closer to neutral.
talk to you soon,
Jon