New forum member here, been lurking here, at androidcentral, and at mydroidworld since I switched to the Bionic from an iphone 3gs.
5.9.901 is better with 3g/4g, but still drops data for me, battery life is the same as it has always been. Need to airplane mode cycle maybe once every other day to regain data when it drops.
5.5.886 (factory install) was terrible, random reboots like twice a day, data always dropping, BlackSOD's, necessary battery pulls, all sorts of awful stuff.
5.5.893 (current official OTA update) fixed all my reboot and BSOD problems, but data was still constantly dropping, requiring airplane mode cycles to regain data connectivity.
5.7.893 was only marginally better than 5.5.893 with data, if at all. Constantly required airplane mode cycles to regain data, upwards of six times a day.
5.9.901 tricked me at first into thinking all data problems had been fixed, but sadly it still drops 3g/4g to the point of requiring an airplane mode cycle
Here's to hoping that Motorola's software engineers can iron out their code sometime soon so they can get the ball rolling on ICS!
BTW been rooted on every firmware release, official or otherwise. Despite its many problems, I still <3 my bionic and feel like it's as much of an upgrade from my 3gs as the 3gs was from my rotary wall-phone.