Here's my regimen - opti coat is permanent so you have none of the reapplying...I used rejex for years...great stuff -
It is so easy to get 2x the pop out of your pipes with the right tools. The tool that makes this work is called a Mother's Power Cone avail at any parts store. You can do this in 10 min with a drill, no sweat at all. The Borla exhaust metal polish is great - off amazon. Apply the paste to the cone, stick it on the drill, and power away. You can not do it too much but 10 secs on each pipe will get results...Once polished, buff it off and spray with alcohol to clean it and apply a few drops of opti coat if oyu want to seal inthe gloss (optional) ...done for months...the soot now will just wipe of easily, gloss is preserved.
Before - these are clean and scrubbed:
But wow! they can get much better polished:

And they really pop from far away now...as they were meant to be...
and optional, a few drops of OC 2.0:
BTW, the power cone is fantastic for wax on wheels....
Mods (overflow) - please move this thread to washing/detailing....