i've had 4 BMWs (and going on 5 soon) and I wouldnt say any of them had problems with reliability. Some electrical issues here and there and a few items replaced under warranty, but luckily with these boards, you'll know of all the problems upfront.
As long as you keep up with maintenence, the car will last well over 100k miles. You get 4 years to have the dealership fix any problems you have anyways. Lexus is reliable, BUT they don't handle as well as BMWs.
I agree that the options will inflate the price, but there are plenty of us here, if you want our opinions. 6FL is mandatory for me since I only use my iPod in my car.