Spoken like a true non-gearhead. Give me all the power! It most certainly is noticeable and there gets to be a point where it is enough. I am not quite there yet. I think about 500whp in a SLK is that point for me. A 200 is fine for some, each person has different preferences.IMHO a 10% power increase is worthless outside of a rules based racing class. You might "think" you feel the added power for a few days or weeks, but then it will feel normal, and there will always be faster cars on the road from people far less sane about demonstrating it.