Anyone with needle scaler experience?

As a Welding shop owner; I've seen guys run them with expert control and no marks afterwards. I've also seen rookies use then on sheet metal and wear holes right thru steel plate and destroy parts.
As anything use the correct tool for the job. A small sandblaster with proper safety gear will not get you in trouble as quickly and will be way more manageable for cleaning rust than a HD tool.
Joe
NOTE: Proper safety gear is a sandblasting hood, eye protection, ear protection and fresh air breathing protection. Also, proper gloves and long sleeve shirt.
Even with proper gear - accidents happen. Take your time and go slow and have a back up plan incase of an accident. Good luck!