I'm running a game that has a player as The Show, and they seem to be enjoying it so far. It's definitely a high mind-share character as you say. They have the tools for causing trouble but not getting out of it like the Battlebabe, and the lack of external motivation like the Skinner so it's not one for the faint of heart. The player needs to be willing to cause chaos and surf the resulting tidal wave to get full enjoyment from the playbook.
The leash holding has worked out fun so far; the Driver holding the leash is never happy when they're asked to spend 3-barter on lifestyle for another character, but the occasional influx of 10-barter is making it worth it, for now. Crack Open the World hasn't seen much use, save for boosting allies in battle. I think that's partially because a lot of the options reference stuff the MC does that the players might not understand, and it being seen as a bit of a nuclear option.
Overall, so far so awesome. Check out AP: Steel City for the sitch with regards to my game, and what The Show has been up to, got another session coming up that should be written up by Thursday.