Overall BMWs have very good driving experience. It's not a matter of 飄 or not. Mercedes will be more solid on highways and even VW are very solid. As a matter of fact, all German cars are solid on highways because there is no speed limit on German Autobahn.
What makes BMWs unique is their excellent handling and road feedback, including 325, and in some cases power.
However, BMW auto transmissions are either GM or ZF made and are not known for long life.