Spun Out reduces the final beatmap's pp by 5%.SpunOut shouldn't reduce pp by flat percentage, but rather the total amount of length of the spinner(s) or total number of spinner(s) or both instead.
While this may sound silly, I'm planning to use SpunOut to make a HD+HR+FL+SO scores so that I can actually enjoy getting SS with such mod combinations on certain map(s) while preventing myself from taking #1 away from players who have HD+DT or DT+FL scores. Would be weird that I got less pp when the map has 0 spinners, isn't it?