The phone comes preset on Automatic, at least mine was, so I wasn't sure.
Also, I have noticed that I do have a tendency to drop calls when driving and the handset switches from tower to tower. Sometimes just gets choppy, but others it will drop.
Didn't notice it initially because I don't talk alot when I drive.
Also, just started having texts fail at going through occasionally. They'll usually go through immediately on retry, which is odd too.