I don't think the kids are that different. I moved after teaching 4th for 10 years up to 5th this year. So far, there hasn't been much difference at all. The things that worked with 4th graders, still work with 5th graders. The teachers tell me the hormones will start kicking in during the spring, so maybe my opinion will change a little.
The one real difference I see is that you will spend a lot of time getting them to "grow up" in the 4th grade. 4th Grade is really a transition year between the primary and the intermediate. I gave a lot of "first B's" so that can be hard. I also spent a lot of time getting kids to be more organized and more independent with their work.
Good luck in your decision.
