I always struggle with upgrades when cars are clearly very capable to begin with.
Follow me for a second ??
Let's assume your car does ~185mph now. We all know that aerodynamics works according to the cube law (to double speed = you need a cube of the power). So your new 480hp will make you go ~10mph faster.
What / When / how often will you be really working in the area from 185-195 ? Not a lot I'll wager.
Also, you're going to get a noticeable torque increase and decrease the 0-60 time by (say) 0.5 second. That's impressive. You'll also reduce those all important in-gear times by a second or two.
So, what (exactly) are you going to do in your life with that extra second / half second you've suddenly gained. ? I'd be interested.
If you had a Ford Escort Mk1 and decided to go from 57hp to 480hp, I'd get the reasoning a little better, but to go from impressively fast to every so slightly more impressively fast just confuses me. I think the marketing people @ these tuning companies have got a lot to answer for.