My comments are all in good fun, although the basics are honest

. I understand what you're saying, but unless you're talking about a motorcycle, 150hp just isn't enough to do much with. The miata is a good example of a low HP, light car. It does very well on an autocross course, but on the street (where it will spend the vast amount of it's time) it's just not enough. Try it out on a track like The 'Ring and see how much fun it is compared to higher HP cars. You'll spend all week getting down the straights.
I've participated in your example on several occasions. I autocross my Cobra once a month, and I'll often co-drive with a friend who has a 2002 Toyota Celica GT. In this example, I'm going from a 3660lb (without me in it) car with 510hp/530tq to a 2400lb car with 140hp/125tq. Like you said, it's kind of fun to toss around a parking lot, but get it on the street and it's really no more than mildly entertaining. Have you participated in a like situation?