If they are a pain and $$$ to replace, it is (mostly) NOT your time and your money. For 4 years it will be fixed under warranty.
By getting them, at least you will use them for at least 4 years. If they fail after that, is just like if you never had them...
I think that a lot of times we make a big issue out of small issues that in other areas of our life are taken as "normal". Water heaters have been around for over 100 years, and I still have had them failed in my home over the years, same for AC units, garbage disposals, toasters, vacuum cleaners, etc. You name it, whatever it is, it will fail at one point. What you should be thankful is that when your BMW fails for whatever reason, it will be fixed under warranty, at no cost for the next 4 years. Try that with almost any other stuff around your home.
As vehicles get more complex, there are more things that can go wrong. Do you realize that there are several computers running almost non-stop in your car, nearly 20x faster than any computer you have around, communicating nearly at the speed of light (that's why they use fiber optics instead of regular wiring on the main computers in your car), and still, our cars work flawlessly nearly all the time. With the number of components in the car, that means that to get a 99% reliability, the individual components need to be flawless 99.999999% of the time.
If you ask me, it is EXTRAORDINARY how incredibly precise and reliable these cars are in spite of all they do all the time. Maybe I've been lucky, but my 2011 535 worked perfectly for 14 months and 14,000 miles until I traded it in. Same for my 2008 328xi, which I had for 3 years and over 40,000 miles (other than a fuel sensor replacement under warranty).
Comparing the reliability of my BMW's with cars I had before (Mercedes Benz, Porsche and Audi), BMW's have been waaaay better. No comparison. And if you start comparing with lesser brands (Chrysler, GM, Ford, etc.) it's not even remotely close.
Heck, even my kids bicycles have had more issues than my BMW's, and they are way simpler... but still have had to adjust the chain, fix the brakes and tighten the kick stand! :rofl: