I did do a search on this topic but did't find any real sollutions.
I, and others here at work with droids, have had some serious issues with flaking out 3g coverage. One day, I'LL have great 3g coverage while my coworker will have 1x coverage that shoots up to 3g 4bars, then instantly drops right back to 1x again. This happens over and over again with no real reasonable cause. Then, the same thing will happen to my Droid on a different day, the same condition.
Thinking it is a service issue, I called verizon to inquire. After talking to their 1st level tech, they forwarded me to a higher level tech. She confirmed the fact that the service in the area was strong, but my, or my coworkers phone was constantly switching from 3g to 1x by looking at how the signal was hitting their "Switch".
She suggested that I do a factory reset on the Droid to see if this helped. And, Viola, it worked! Now, I had perfect reception, 3g with 4 bars! She waited on the phone with me for a few minutes longer just to confirm that it was acting normal. She later left me a voice mail explaining that her boss has the same problem with his Droid and it is an equipment issue that will hopefully be fixed with a software update.
Which leads me to today, the same issue again! So again I called Verizon techs and explained that this is a real pain to have do a factory reset every time this happens. This time they suggested for me to remove my battery while they killed my service line on their end. Once the service line was disconnected, they had me really install my battery and reprogram the phone by dialling 228. This has also worked to cure my Droid of spastic 3g signal strength.
BUT, one thing is for sure, it does seem to be a problem with the Droid. Either a glitch in the software or an actual flaw in the ability for some droids capturing and holding a 3g signal.