Signal fluctuation and droid type phones

I have had many complaits of our signal jumping up and down after people are getting one of the droid type phones. I know signal flucuations are nomal.
Has anyone else had issues with almost all types of droid type phones showing signal fluctuation?
If so do you know why? could this be a more sensitive receiver? could the bars just have a closer db reading? for example 1 bar is a -102 to -99.
2 bars is -98 to -96…