Some more elitist crap here, but I find it disconcerting that the aftermarket parts industry has basically made it so people think anything that says "coilover" on it is automatically something that will make their car better. I understand the OP still has his stock suspension. But what I don't understand is removing a well designed, high quality suspension setup with tons of great engineering behind it, and replacing it with unknown dampers, secret spring rates, no adjustable dampening, ect.
Coilovers are designed for people that require the extra adjustability of being able to pick spring rates they want, set dampening properly to accompany those spring rates, set ride height at proper ranges to optimize roll center, suspension travel, and rake, balance the weight of the car, then use camber plates in conjunction with stock adjustments to align the car properly in supplement to the suspension setup.
It's nice to experiment. But did you find out what the spring rates are on these and how they compare to stock? Do you know how much travel the dampers have and whether or not your ride heights are going to bottom them out in compression or droop? Did you measure the stock ride heights before removing stock suspension so you could reproduce any right to left bias built in to compensate for driver weight, then calculate compression at your new spring rates with you in the car so sway bar preload isn't an issue? Did you disconnect the sways when setting ride heights so the ride heights could be set without them interfering and you could check for preload at the new heights? Did you measure damper travel to be sure you're not riding on your bump stops? Did you record ride heights so you can check and make sure the adjustment collars aren't slipping and messing up your alignment? What specs did you align the car to? Did you reset the preload on the RTABs and other bushings so there not twisted at the new ride height?
Those are the things you need to take into consideration to properly set up a suspension setup with adjustable ride height. If you ignore that stuff, you're really just playing with the car, downgrading from what BMW put on it, and possibly causing issues as well.
I'm not trying to attack you personally. But I see too many people that are the product of ill-informed information that gets regurgitated over and over again. Pulling well designed suspension off a $50K BMW to throw a $500 spring and damper kit with threaded collars on it? Meh.
You have a great car. An amazing car. In the future, I'd urge you to learn about the engineering before you change it. Learning doesn't cost anything.