I saw one at a local auction and spent some time going down the rabbit hole of investigating if it would work better than manual or media paint and/or rust removal.
I watched about 10-12 videos of them in operation and testing on YouTube and came to the conclusion that there was nothing that warranted me spending several thousand on the used laser at the auction vs what I could already do.
It looks cool, but based on what I watched, pretty limited in its usage.
And, like TominCologne said, if you're looking at one of the low-end ones from Amazon, it will not likely do much at all.