I've never had it as a power up myself, but it's basically F1RS's version of the blue shell in Mario kart. I.e. It's a big "screw you" to whoever is in the lead. The difference is that it doesn't automatically grant someone else a better place. Like in real f1, it bunches up the pack, creating a really tight fight for the lead. I prefer it to the blue shell because the leader has a fighting chance to keep their place.