I had a child-size Aerobed when my youngest was 2-3. I liked it for him because it had slightly higher sides that helped keep him in the bed, it wasn't so easy for him to roll off the sides. The only bad thing about it was that if he woke up, he'd just come stand by my side of the bed and stare at me until I woke up. It's so unsettling to wake up, open your eyes and see someone staring at you! Then, I'd wind up pulling him into bed beside me so we could get some more sleep.
My boss's wife bought that Aerobed from me and uses it with their grandchildren when they visit and she's told me how much the kids love sleeping on it. It suited the purpose I needed at the time.