it really is not good, if you run the graphs it completely drains battery way too fast. also the switchstyle system is a joke. youll also get a bug where you lose service at random points and it will go back to searching for it for a few seconds then find it again.
I always thought battery saving apps were a good idea, and after extensive use of them for almost 6 months, i 86'ed them. They are a joke IMO. Find a good app/tweak to give you quick access to all of you RADIO SWITCHES and learn how to activate them manually.
If you must use an App to do this, the only one I recommend is Auto3G, but if you have an IP5 this wont help.