I have a buddy that used to have a Model IV with dihedral that he said reminded him of a diving pigeon. He hated the look. When I was building my first IV I asked the factory the difference in performance since the early IV Speedster also had no dihedral. I was told - no difference. I reduced the dihedral, but did not eliminate it. Then recently I read an article in Kitplanes Magazine discussing "Dihedral Effect". Essentially, Wing dihedral is critical in low wing airplanes, but not so much in high wing airplanes. With a high wing a side slip will create high pressure under the up-wind wing due to the fuselage being below the wing and low pressure under the down-wind wing for the same reason resulting in a favorable roll tendency. This effect is missing (actually potentially reversed) with a low wing airplane. This necessitating dihedral on low wing airplanes. My first IV had minimal dihedral as I built it from day one. The one I fly now had the wings installed by the first builder and somewhat resembles the diving pigeon. With my two Model IVs, I perceive no difference in handling.