I primarily use 3G all day for calls and GPRS. 2G on my SIM card (China) is not great so I resort to keeping the phone on 3G since it's a 3G card. I've tried "dual" and "GSM" and it seems dual is the best setting for me. I also never, ever use GPS nor bluetooth and I dont have any widgets that connect or update. and my internet connection is set to Always Ask. I never use Wifi at all either, heard conflicting reports as to which uses more power (wifi or 3g gprs). I'm guessing it has to do with the telecom towers here, maybe theyre not strong enough. 3G is a new service in my area....