I was using juice defender for a long time and getting very good success. My battery would easily last over 24 hours.
However, I was told about switch pro. Its like the power control widge accept it has many more options like turning 3g on and off... I basically keep 3g off unless I am browsing. using this app it has now been 36 hours since unpluged and I am at 25% battery. That with about 20 calls, 30 text messages, and an hour of web browsing.
I highly reccomend switch pro. It is not a good fit for you if you need push notifications. I don't need that so this is perfect for me. If you need push notifications stick with juice defender.