Paint & Body Work - Do dent pullers work

Just curious if those little autozone dent pullers work or is it just a waste of time?

I'm not sure if they're the same or similar, but I tried the Pops-A-Dent once and it sucked. I ended up calling a dent removal company.

i wouldn't waste my money, as i would just have a shop do it, unless.... you plan on getting dents often. what size dent? if its just like hail damage get the panel hot and use dry ice