This is what I've been doing on my Asus Transformer for quite a while...I get great battery life with it, and now I'm trying it on my DroidX. The only problem that I have is that it takes at least 20 seconds after tapping Data Manager to get to the Background Data setting. I also uncheck Enable Data while there! Anyone else experiencing this amount of time for the settings to come up? I should mention, though, I'm rooted and still on Froyo...and too chicken to install any ROMs.