Mercedes Benz Maintanence Cost and Reliability

Lmao I see what you did there...

All I can speak to is my own experience. My 2014 Cla 250 had an unusual number of problems. Prior, I had a Jetta diesel, that also had an unusual number of problems.
I owned the Jetta for 5 years, it had a blown turbo, complete exhaust sys replacement (probably a consequence of the blown turbo) , alternator, rear window motor,
all this, under warranty. The dealer almost talked me into a 4K out of pocket DPF storage cat replacement (fixed via Italian Tune-up: driving the at higer rpm-s for a while)
At which point it was time to part with the car: do I really want a $4k Damocles sword hanging over my head?

I swore never a German car again, but got seduced by the cla 250. "It is 2014 now, surely they worked out all the kinks, what could possibly go wrong?".
This car spends a fair amount of time at the dealer.
Failed water pump at 24K, various engine computer problems. Brake pulsing (front pads and rotor replaced 2x) . Left rear speaker blown ( Harman Kardon radio). Radar sensor replaced.
After water pump work, the car developed a rattle/rumble in the engine compartment. Dealer claims, this is now fixed. I say, nay! If the car needs any parts, it is a 1-2 week wait, to be shipped
from Germany.
So far, I have been covered under warranty, and usually they give me a nice loaner. The only thing that was somewhat painful is having to listen to my wife because
the car had to be towed when she was driving it. (the water pump affair...)

Looking at the repair costs (which they tend to put down on the work orders), all these repairs would have been very expensive, if I had to pay out of pocket. E.g.:
Water pump: parts and labor $800.
Dealer maintenace, "A" service: "The home of the $185 oil change" They say: it is a lot more than an oil change. I say, it _is_ an oil change, evidenced by the work order.
"B" service: Oil change, cabin air filter, brake fluid change. $385. (Truth be told, I prepaid $800 for 2x A and 2x B.)
Oh.. almost forgot rhe run-flat tires. I hate to think of the procedure should I pick up a nail. Probably involves bending over.
The user's manual says something about driving to the dealer, should that happen.

So: How costly is this car going to be, once you are out of warranty? ( Say, compared to some common sense car?).
Obviously you could just let the little things go. Parking sensors? Stereo? Noises? Just live with it.
Try to fix anything you can fix... But these cars are not easy to work on. Try to get a factory service manual?
Brakes, oil change, filters: doable. The parts cost 2-3x of an Asian/Domestic car.

Dont get me wrong: I love German cars. They drive like nothing else out there. But my 2c is : From my experience, they appear unreliable and expensive to repair.

I have had no issues with my CLA45 since I bought it almost a year ago other than an issue with the pause/mute button which required a reinstall of the system (which was free). I don't know how much more expensive this car will be as it gets older, but I went in fully expecting a more expensive maintenance bill.

With regards to the discs being warped, I think other people had issues with that. You may want to browse the forum. I don't think it ended up being a disc issue.

As to the HK system, I think it has more than enough bass. I don't usually go around with the bass thumping (I don't like my cars to shake and rattle) but it definitely goes high enough on my car for me to hate it. Personally I think quality audio systems in a car are overkill since there is so much background noise from the car/road/air and for the most part we play 128kbps mp3s from streaming sites. Even 320kbps only gets you so far. A really good audio system can't really shine unless you are using uncompressed music like from a CD (or at least lossless formats). I'm always amazed by people who will spend hundreds of dollars on expensive headphones only to listen to 128kbps audio from iTunes. Heck I had music in the late 90s when I was a schoolkid that were higher quality.