NudeCactus, the world record holder for this category at the time of upload, challenged me to get a sub-30-minute time in this category, and I accepted. I got this run going about 45 minutes into my first attempts and rode it all the way home, earning myself 20th place on the leaderboard.
This was fun, but I'm not really feeling any% Mushroom as a category, I have to say. It's much more likely that I'll do any% Special if I'm really intent on speedrunning this game after I (hopefully!) get the 7/7 Superstar% records. All the same, I'm really glad that I was challenged to do this!