The big thing use to be powder coating. I remember when it first came out, they said you would dent the steel before you could scratch the powder coating. But now I watch tv shows building bikes and they are always scratching the new powder coating. Is it as strong as they say ? I dont know. A good paint job will last a lifetime , until you scratch it, which will happen on the tube fenders or rails. Paint does scratch easily. I would do a nice etching primer first. And then just use a quality satin gloss black spray paint. SEM makes the best, I think but its like $12 a can. Wurth also makes a good product. The thing is its EASY to touch up. Even if the piece is originally powder coated black, you can easily touch it up with some spray paint.