I have had my RAZR Maxx HD for about 3 months (previous phone was the Droid X). It has been a great phone. Always have good signal strength & usually get 2 days battery life. The only down side to this phone is the camera, which works fine in the daylight, but low light & indoors not the best. The camera was not the reason I bought the phone, it was because of the good signal strength (like the Droid X), long battery life, & closest to vanilla Android.
There also had been reports on the forums of the S3 having poor signal strength in rural areas & areas with weaker signal.
I would choose the RAZR Maxx HD again.