I'm looking at these two portables, each retailing about $99. What's the difference? I've gone online and they seem very similar. Is one an older model?

Also, they both run on 'AA' batteries. Is this a new thing? The portables I've always had in the past ran on 'C' or 'D' batteries. Do the 'AA' batteries need more frequent replacing?

Thanks in advance.
Music School Owner
Early Childhood Music Teacher/Group Piano Teacher/Private Piano Teacher
Member of MTAC and Guild