Sunny and Tycoon......that's a bit harsh, no? The M3 is really a road car with a lot of performance packed in. I agree that for the track junkie, the M3 cabrio is a waste of money, but for those who want a very good performing car with the luxury of open top for the road and even on occasional track days, it delivers more than enough for the average driver.
Now, you may wonder, why not just get a 335i cabrio instead??.....much cheaper, more than enough performance for the road, etc, etc. Well, you don't get the wonderful V8, and you don't get things like adjustable dampers and the cool M-DKG gearbox.
Saying the M3 cabrio is pointless is like saying all high priced luxury cars are really pointless.........some people in this world indeed feel this way, but I don't think you two fall into that category.