My oldest dd rode it when she was around that age and while I thought she'd HATE it...she absolutely loved it and wants to ride it again and again every year. Not TOT is another story LOL But then she's a lot like me in that respect. I can do coasters all day, just don't drop me from anything high repeatedly LOL
My youngest dd will be almost 6 during our trip (a month away from 6 actually)....so I'm wondering how 'ready' she'll be to ride it then. She wants to ride everything her big sister rides....and rode test track last year, but I consider it mild compared to RNR. We may have to wait and see, it's just really so individual with each one of them.