Okay but that's just describing what the acid in it does, the same that would happen with a home brew.Iron remover actually creates rust that expands the embedded iron particles and removes the sharp spikes in the iron then when washed off loosens the iron. Thanks… Try a plastic bag on your hand on dry paint, before and after. You will be able to feel the contanimation.
I suppose if you detail cars for a living, a bottle of expensive, professional looking product creates a good appearance to customers, but if you just have a little rust to get off a personal vehicle, 32 oz of vinegar is $1 at Walmart and a dozen times more than needed to do a typical vehicle.
Once you have the vinegar, you can put the DIY solution in the professional looking spray bottle.