Porsche Cayenne 2006 250hp petrol Repro stage 1?

I just knew about the stages and repro things a few days ago and the guy who does it for everyone around me (rsq3) (gle’s) etc told me it’s available for my cayenne and will add like 50hp, less fuel consumption and better sound (what I want) but I was thinking if it’s a good idea or not regarding the vehicle reliability after doing the stage 1 maybe it’ll broke down or smt since the car is “forced” he charges me 450€, do you think It’ll be a good idea? Thanks