It's not worth it unless you are trying to keep heat off fragile underhood components that run close to your exhaust. I have seen wraps help in turbo applications (help turbo spool faster and keep underhood temps down). In an N/A application they have very minimal advantages except for what I mentioned in sentence #1.
IMHO, they are an antiquated crutch method compared to more modern coatings which are much much superior.
Wraps also greatly reduce the life of your exhaust components (stainless or not).
So, in my opinion, stay away from them. Stick with coatings.