share your exp with delete tuning

Hi, everyone!
I came across this delete tuning thing on the web.
Dudes promise performance boost by removing various factory restrictions.
They are pretty much, here's an example (no bans please, thats only for clarity)
https://dpfdelet.com/
Please share your experience, what is it, what are the pitfalls, what power increase you managed to reach (if used it), and whether it is worth getting involved at all.
If I do understand right, installation of such equipment imposes a lot of restrictions?

 

Will it pass emissions inspection?

 

This is for diesel trucks.

Same as deleting your catalytic convertors in a way, but unlike on your Tacoma, on a diesel its a restriction

 

https://www.epa.gov/enforcement/clean-air-act-vehicle-and-engine-enforcement-case-resolutions

Deleting emissions equipment has consequences. Agree with it or not.