Sanding a plastered drywall surface

Original title: This is one of those gadgets where like I really wanted to work and I really want to learn how to use it but when it comes to certain things it just doesn't work very well. But when it comes to other stuff like around doors and windows it works pretty well. But if you have any inconsistencies and like you're ceiling or in your baseboard it just doesn't do it very well at all and you end up having to go back and do stuff with a brush. Anyway. What do you guys think of these things? #HomeImprovement #diy #construction #builder