So this is an interesting thread. The "anti" MR claiming the cost to repair which, yes, will cost more. But that being said, I'm not sure where 50,000 miles comes from, nor the cost of $3,000. Both seem way off to me, but I've not done the research. But if you are remembering the 70s when shocks were done with the frequency of brakes and tires then maybe you need to reset the clock.
It is a wonderful feature if you want a hard ride in sport mode BUT also want a comfortable ride while being your DD.
I have a 2014 SS. They didn't add MR shocks until 2015. I can assure you for what that car does and what I expect, I don't feel lacking.
A base car should be tuned well enough to be do what it's mission is. Problem is, a car tuned ideally for the track will not be comfortable on the road and vice versa. MR is a technology that helps optimize across a wider band.
It comes from all the rest of the people that have replaced these shocks.