most sources now are all against smoke because of the image it gives diesel, which is not a horrible thing, but you cant always believe them when they say what part you MUST use to make more power. chips/programmers are usually what they are most biased about, same with ‘cold air intakes’. they will also have mile long article telling you what exhaust is better when there isnt one that will make any more power than eliminating your cat/muffler and using the rest of your stock pipe