I booked one for the Tomorrowland Speedway for my mom and niece while everyone else rides Space Mountain. I would've done Buzz but everyone else has a FP for that anyway. But either one of those would be good.
My DH has a FP for Space Mountain. I have no desire to ride it, so I booked Tomorrowland Speedway for the same exact time for my and my daughter (age 12). It should work out perfect! I would of done Buzz, but my DH will want to ride that and he is OK with skipping the speedway.